SELinux: Don't flush inherited SIGKILL during execve()
[linux-2.6.git] / security / selinux / hooks.c
1 /*
2  *  NSA Security-Enhanced Linux (SELinux) security module
3  *
4  *  This file contains the SELinux hook function implementations.
5  *
6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
7  *            Chris Vance, <cvance@nai.com>
8  *            Wayne Salamon, <wsalamon@nai.com>
9  *            James Morris <jmorris@redhat.com>
10  *
11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13  *                                         Eric Paris <eparis@redhat.com>
14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15  *                          <dgoeddel@trustedcs.com>
16  *  Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
17  *              Paul Moore <paul.moore@hp.com>
18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
20  *
21  *      This program is free software; you can redistribute it and/or modify
22  *      it under the terms of the GNU General Public License version 2,
23  *      as published by the Free Software Foundation.
24  */
25
26 #include <linux/init.h>
27 #include <linux/kernel.h>
28 #include <linux/tracehook.h>
29 #include <linux/errno.h>
30 #include <linux/sched.h>
31 #include <linux/security.h>
32 #include <linux/xattr.h>
33 #include <linux/capability.h>
34 #include <linux/unistd.h>
35 #include <linux/mm.h>
36 #include <linux/mman.h>
37 #include <linux/slab.h>
38 #include <linux/pagemap.h>
39 #include <linux/swap.h>
40 #include <linux/spinlock.h>
41 #include <linux/syscalls.h>
42 #include <linux/file.h>
43 #include <linux/fdtable.h>
44 #include <linux/namei.h>
45 #include <linux/mount.h>
46 #include <linux/proc_fs.h>
47 #include <linux/netfilter_ipv4.h>
48 #include <linux/netfilter_ipv6.h>
49 #include <linux/tty.h>
50 #include <net/icmp.h>
51 #include <net/ip.h>             /* for local_port_range[] */
52 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
53 #include <net/net_namespace.h>
54 #include <net/netlabel.h>
55 #include <linux/uaccess.h>
56 #include <asm/ioctls.h>
57 #include <asm/atomic.h>
58 #include <linux/bitops.h>
59 #include <linux/interrupt.h>
60 #include <linux/netdevice.h>    /* for network interface checks */
61 #include <linux/netlink.h>
62 #include <linux/tcp.h>
63 #include <linux/udp.h>
64 #include <linux/dccp.h>
65 #include <linux/quota.h>
66 #include <linux/un.h>           /* for Unix socket types */
67 #include <net/af_unix.h>        /* for Unix socket types */
68 #include <linux/parser.h>
69 #include <linux/nfs_mount.h>
70 #include <net/ipv6.h>
71 #include <linux/hugetlb.h>
72 #include <linux/personality.h>
73 #include <linux/sysctl.h>
74 #include <linux/audit.h>
75 #include <linux/string.h>
76 #include <linux/selinux.h>
77 #include <linux/mutex.h>
78 #include <linux/posix-timers.h>
79
80 #include "avc.h"
81 #include "objsec.h"
82 #include "netif.h"
83 #include "netnode.h"
84 #include "netport.h"
85 #include "xfrm.h"
86 #include "netlabel.h"
87 #include "audit.h"
88
89 #define XATTR_SELINUX_SUFFIX "selinux"
90 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
91
92 #define NUM_SEL_MNT_OPTS 5
93
94 extern unsigned int policydb_loaded_version;
95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
96 extern struct security_operations *security_ops;
97
98 /* SECMARK reference count */
99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
100
101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
102 int selinux_enforcing;
103
104 static int __init enforcing_setup(char *str)
105 {
106         unsigned long enforcing;
107         if (!strict_strtoul(str, 0, &enforcing))
108                 selinux_enforcing = enforcing ? 1 : 0;
109         return 1;
110 }
111 __setup("enforcing=", enforcing_setup);
112 #endif
113
114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
116
117 static int __init selinux_enabled_setup(char *str)
118 {
119         unsigned long enabled;
120         if (!strict_strtoul(str, 0, &enabled))
121                 selinux_enabled = enabled ? 1 : 0;
122         return 1;
123 }
124 __setup("selinux=", selinux_enabled_setup);
125 #else
126 int selinux_enabled = 1;
127 #endif
128
129
130 /*
131  * Minimal support for a secondary security module,
132  * just to allow the use of the capability module.
133  */
134 static struct security_operations *secondary_ops;
135
136 /* Lists of inode and superblock security structures initialized
137    before the policy was loaded. */
138 static LIST_HEAD(superblock_security_head);
139 static DEFINE_SPINLOCK(sb_security_lock);
140
141 static struct kmem_cache *sel_inode_cache;
142
143 /**
144  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
145  *
146  * Description:
147  * This function checks the SECMARK reference counter to see if any SECMARK
148  * targets are currently configured, if the reference counter is greater than
149  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
150  * enabled, false (0) if SECMARK is disabled.
151  *
152  */
153 static int selinux_secmark_enabled(void)
154 {
155         return (atomic_read(&selinux_secmark_refcount) > 0);
156 }
157
158 /*
159  * initialise the security for the init task
160  */
161 static void cred_init_security(void)
162 {
163         struct cred *cred = (struct cred *) current->real_cred;
164         struct task_security_struct *tsec;
165
166         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
167         if (!tsec)
168                 panic("SELinux:  Failed to initialize initial task.\n");
169
170         tsec->osid = tsec->sid = SECINITSID_KERNEL;
171         cred->security = tsec;
172 }
173
174 /*
175  * get the security ID of a set of credentials
176  */
177 static inline u32 cred_sid(const struct cred *cred)
178 {
179         const struct task_security_struct *tsec;
180
181         tsec = cred->security;
182         return tsec->sid;
183 }
184
185 /*
186  * get the objective security ID of a task
187  */
188 static inline u32 task_sid(const struct task_struct *task)
189 {
190         u32 sid;
191
192         rcu_read_lock();
193         sid = cred_sid(__task_cred(task));
194         rcu_read_unlock();
195         return sid;
196 }
197
198 /*
199  * get the subjective security ID of the current task
200  */
201 static inline u32 current_sid(void)
202 {
203         const struct task_security_struct *tsec = current_cred()->security;
204
205         return tsec->sid;
206 }
207
208 /* Allocate and free functions for each kind of security blob. */
209
210 static int inode_alloc_security(struct inode *inode)
211 {
212         struct inode_security_struct *isec;
213         u32 sid = current_sid();
214
215         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
216         if (!isec)
217                 return -ENOMEM;
218
219         mutex_init(&isec->lock);
220         INIT_LIST_HEAD(&isec->list);
221         isec->inode = inode;
222         isec->sid = SECINITSID_UNLABELED;
223         isec->sclass = SECCLASS_FILE;
224         isec->task_sid = sid;
225         inode->i_security = isec;
226
227         return 0;
228 }
229
230 static void inode_free_security(struct inode *inode)
231 {
232         struct inode_security_struct *isec = inode->i_security;
233         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
234
235         spin_lock(&sbsec->isec_lock);
236         if (!list_empty(&isec->list))
237                 list_del_init(&isec->list);
238         spin_unlock(&sbsec->isec_lock);
239
240         inode->i_security = NULL;
241         kmem_cache_free(sel_inode_cache, isec);
242 }
243
244 static int file_alloc_security(struct file *file)
245 {
246         struct file_security_struct *fsec;
247         u32 sid = current_sid();
248
249         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
250         if (!fsec)
251                 return -ENOMEM;
252
253         fsec->sid = sid;
254         fsec->fown_sid = sid;
255         file->f_security = fsec;
256
257         return 0;
258 }
259
260 static void file_free_security(struct file *file)
261 {
262         struct file_security_struct *fsec = file->f_security;
263         file->f_security = NULL;
264         kfree(fsec);
265 }
266
267 static int superblock_alloc_security(struct super_block *sb)
268 {
269         struct superblock_security_struct *sbsec;
270
271         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
272         if (!sbsec)
273                 return -ENOMEM;
274
275         mutex_init(&sbsec->lock);
276         INIT_LIST_HEAD(&sbsec->list);
277         INIT_LIST_HEAD(&sbsec->isec_head);
278         spin_lock_init(&sbsec->isec_lock);
279         sbsec->sb = sb;
280         sbsec->sid = SECINITSID_UNLABELED;
281         sbsec->def_sid = SECINITSID_FILE;
282         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
283         sb->s_security = sbsec;
284
285         return 0;
286 }
287
288 static void superblock_free_security(struct super_block *sb)
289 {
290         struct superblock_security_struct *sbsec = sb->s_security;
291
292         spin_lock(&sb_security_lock);
293         if (!list_empty(&sbsec->list))
294                 list_del_init(&sbsec->list);
295         spin_unlock(&sb_security_lock);
296
297         sb->s_security = NULL;
298         kfree(sbsec);
299 }
300
301 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
302 {
303         struct sk_security_struct *ssec;
304
305         ssec = kzalloc(sizeof(*ssec), priority);
306         if (!ssec)
307                 return -ENOMEM;
308
309         ssec->peer_sid = SECINITSID_UNLABELED;
310         ssec->sid = SECINITSID_UNLABELED;
311         sk->sk_security = ssec;
312
313         selinux_netlbl_sk_security_reset(ssec);
314
315         return 0;
316 }
317
318 static void sk_free_security(struct sock *sk)
319 {
320         struct sk_security_struct *ssec = sk->sk_security;
321
322         sk->sk_security = NULL;
323         selinux_netlbl_sk_security_free(ssec);
324         kfree(ssec);
325 }
326
327 /* The security server must be initialized before
328    any labeling or access decisions can be provided. */
329 extern int ss_initialized;
330
331 /* The file system's label must be initialized prior to use. */
332
333 static char *labeling_behaviors[6] = {
334         "uses xattr",
335         "uses transition SIDs",
336         "uses task SIDs",
337         "uses genfs_contexts",
338         "not configured for labeling",
339         "uses mountpoint labeling",
340 };
341
342 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
343
344 static inline int inode_doinit(struct inode *inode)
345 {
346         return inode_doinit_with_dentry(inode, NULL);
347 }
348
349 enum {
350         Opt_error = -1,
351         Opt_context = 1,
352         Opt_fscontext = 2,
353         Opt_defcontext = 3,
354         Opt_rootcontext = 4,
355         Opt_labelsupport = 5,
356 };
357
358 static const match_table_t tokens = {
359         {Opt_context, CONTEXT_STR "%s"},
360         {Opt_fscontext, FSCONTEXT_STR "%s"},
361         {Opt_defcontext, DEFCONTEXT_STR "%s"},
362         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
363         {Opt_labelsupport, LABELSUPP_STR},
364         {Opt_error, NULL},
365 };
366
367 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
368
369 static int may_context_mount_sb_relabel(u32 sid,
370                         struct superblock_security_struct *sbsec,
371                         const struct cred *cred)
372 {
373         const struct task_security_struct *tsec = cred->security;
374         int rc;
375
376         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
377                           FILESYSTEM__RELABELFROM, NULL);
378         if (rc)
379                 return rc;
380
381         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
382                           FILESYSTEM__RELABELTO, NULL);
383         return rc;
384 }
385
386 static int may_context_mount_inode_relabel(u32 sid,
387                         struct superblock_security_struct *sbsec,
388                         const struct cred *cred)
389 {
390         const struct task_security_struct *tsec = cred->security;
391         int rc;
392         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
393                           FILESYSTEM__RELABELFROM, NULL);
394         if (rc)
395                 return rc;
396
397         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
398                           FILESYSTEM__ASSOCIATE, NULL);
399         return rc;
400 }
401
402 static int sb_finish_set_opts(struct super_block *sb)
403 {
404         struct superblock_security_struct *sbsec = sb->s_security;
405         struct dentry *root = sb->s_root;
406         struct inode *root_inode = root->d_inode;
407         int rc = 0;
408
409         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
410                 /* Make sure that the xattr handler exists and that no
411                    error other than -ENODATA is returned by getxattr on
412                    the root directory.  -ENODATA is ok, as this may be
413                    the first boot of the SELinux kernel before we have
414                    assigned xattr values to the filesystem. */
415                 if (!root_inode->i_op->getxattr) {
416                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
417                                "xattr support\n", sb->s_id, sb->s_type->name);
418                         rc = -EOPNOTSUPP;
419                         goto out;
420                 }
421                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
422                 if (rc < 0 && rc != -ENODATA) {
423                         if (rc == -EOPNOTSUPP)
424                                 printk(KERN_WARNING "SELinux: (dev %s, type "
425                                        "%s) has no security xattr handler\n",
426                                        sb->s_id, sb->s_type->name);
427                         else
428                                 printk(KERN_WARNING "SELinux: (dev %s, type "
429                                        "%s) getxattr errno %d\n", sb->s_id,
430                                        sb->s_type->name, -rc);
431                         goto out;
432                 }
433         }
434
435         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
436
437         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
438                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
439                        sb->s_id, sb->s_type->name);
440         else
441                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
442                        sb->s_id, sb->s_type->name,
443                        labeling_behaviors[sbsec->behavior-1]);
444
445         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
446             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
447             sbsec->behavior == SECURITY_FS_USE_NONE ||
448             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
449                 sbsec->flags &= ~SE_SBLABELSUPP;
450
451         /* Initialize the root inode. */
452         rc = inode_doinit_with_dentry(root_inode, root);
453
454         /* Initialize any other inodes associated with the superblock, e.g.
455            inodes created prior to initial policy load or inodes created
456            during get_sb by a pseudo filesystem that directly
457            populates itself. */
458         spin_lock(&sbsec->isec_lock);
459 next_inode:
460         if (!list_empty(&sbsec->isec_head)) {
461                 struct inode_security_struct *isec =
462                                 list_entry(sbsec->isec_head.next,
463                                            struct inode_security_struct, list);
464                 struct inode *inode = isec->inode;
465                 spin_unlock(&sbsec->isec_lock);
466                 inode = igrab(inode);
467                 if (inode) {
468                         if (!IS_PRIVATE(inode))
469                                 inode_doinit(inode);
470                         iput(inode);
471                 }
472                 spin_lock(&sbsec->isec_lock);
473                 list_del_init(&isec->list);
474                 goto next_inode;
475         }
476         spin_unlock(&sbsec->isec_lock);
477 out:
478         return rc;
479 }
480
481 /*
482  * This function should allow an FS to ask what it's mount security
483  * options were so it can use those later for submounts, displaying
484  * mount options, or whatever.
485  */
486 static int selinux_get_mnt_opts(const struct super_block *sb,
487                                 struct security_mnt_opts *opts)
488 {
489         int rc = 0, i;
490         struct superblock_security_struct *sbsec = sb->s_security;
491         char *context = NULL;
492         u32 len;
493         char tmp;
494
495         security_init_mnt_opts(opts);
496
497         if (!(sbsec->flags & SE_SBINITIALIZED))
498                 return -EINVAL;
499
500         if (!ss_initialized)
501                 return -EINVAL;
502
503         tmp = sbsec->flags & SE_MNTMASK;
504         /* count the number of mount options for this sb */
505         for (i = 0; i < 8; i++) {
506                 if (tmp & 0x01)
507                         opts->num_mnt_opts++;
508                 tmp >>= 1;
509         }
510         /* Check if the Label support flag is set */
511         if (sbsec->flags & SE_SBLABELSUPP)
512                 opts->num_mnt_opts++;
513
514         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
515         if (!opts->mnt_opts) {
516                 rc = -ENOMEM;
517                 goto out_free;
518         }
519
520         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
521         if (!opts->mnt_opts_flags) {
522                 rc = -ENOMEM;
523                 goto out_free;
524         }
525
526         i = 0;
527         if (sbsec->flags & FSCONTEXT_MNT) {
528                 rc = security_sid_to_context(sbsec->sid, &context, &len);
529                 if (rc)
530                         goto out_free;
531                 opts->mnt_opts[i] = context;
532                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
533         }
534         if (sbsec->flags & CONTEXT_MNT) {
535                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
536                 if (rc)
537                         goto out_free;
538                 opts->mnt_opts[i] = context;
539                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
540         }
541         if (sbsec->flags & DEFCONTEXT_MNT) {
542                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
543                 if (rc)
544                         goto out_free;
545                 opts->mnt_opts[i] = context;
546                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
547         }
548         if (sbsec->flags & ROOTCONTEXT_MNT) {
549                 struct inode *root = sbsec->sb->s_root->d_inode;
550                 struct inode_security_struct *isec = root->i_security;
551
552                 rc = security_sid_to_context(isec->sid, &context, &len);
553                 if (rc)
554                         goto out_free;
555                 opts->mnt_opts[i] = context;
556                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
557         }
558         if (sbsec->flags & SE_SBLABELSUPP) {
559                 opts->mnt_opts[i] = NULL;
560                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
561         }
562
563         BUG_ON(i != opts->num_mnt_opts);
564
565         return 0;
566
567 out_free:
568         security_free_mnt_opts(opts);
569         return rc;
570 }
571
572 static int bad_option(struct superblock_security_struct *sbsec, char flag,
573                       u32 old_sid, u32 new_sid)
574 {
575         char mnt_flags = sbsec->flags & SE_MNTMASK;
576
577         /* check if the old mount command had the same options */
578         if (sbsec->flags & SE_SBINITIALIZED)
579                 if (!(sbsec->flags & flag) ||
580                     (old_sid != new_sid))
581                         return 1;
582
583         /* check if we were passed the same options twice,
584          * aka someone passed context=a,context=b
585          */
586         if (!(sbsec->flags & SE_SBINITIALIZED))
587                 if (mnt_flags & flag)
588                         return 1;
589         return 0;
590 }
591
592 /*
593  * Allow filesystems with binary mount data to explicitly set mount point
594  * labeling information.
595  */
596 static int selinux_set_mnt_opts(struct super_block *sb,
597                                 struct security_mnt_opts *opts)
598 {
599         const struct cred *cred = current_cred();
600         int rc = 0, i;
601         struct superblock_security_struct *sbsec = sb->s_security;
602         const char *name = sb->s_type->name;
603         struct inode *inode = sbsec->sb->s_root->d_inode;
604         struct inode_security_struct *root_isec = inode->i_security;
605         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
606         u32 defcontext_sid = 0;
607         char **mount_options = opts->mnt_opts;
608         int *flags = opts->mnt_opts_flags;
609         int num_opts = opts->num_mnt_opts;
610
611         mutex_lock(&sbsec->lock);
612
613         if (!ss_initialized) {
614                 if (!num_opts) {
615                         /* Defer initialization until selinux_complete_init,
616                            after the initial policy is loaded and the security
617                            server is ready to handle calls. */
618                         spin_lock(&sb_security_lock);
619                         if (list_empty(&sbsec->list))
620                                 list_add(&sbsec->list, &superblock_security_head);
621                         spin_unlock(&sb_security_lock);
622                         goto out;
623                 }
624                 rc = -EINVAL;
625                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
626                         "before the security server is initialized\n");
627                 goto out;
628         }
629
630         /*
631          * Binary mount data FS will come through this function twice.  Once
632          * from an explicit call and once from the generic calls from the vfs.
633          * Since the generic VFS calls will not contain any security mount data
634          * we need to skip the double mount verification.
635          *
636          * This does open a hole in which we will not notice if the first
637          * mount using this sb set explict options and a second mount using
638          * this sb does not set any security options.  (The first options
639          * will be used for both mounts)
640          */
641         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
642             && (num_opts == 0))
643                 goto out;
644
645         /*
646          * parse the mount options, check if they are valid sids.
647          * also check if someone is trying to mount the same sb more
648          * than once with different security options.
649          */
650         for (i = 0; i < num_opts; i++) {
651                 u32 sid;
652
653                 if (flags[i] == SE_SBLABELSUPP)
654                         continue;
655                 rc = security_context_to_sid(mount_options[i],
656                                              strlen(mount_options[i]), &sid);
657                 if (rc) {
658                         printk(KERN_WARNING "SELinux: security_context_to_sid"
659                                "(%s) failed for (dev %s, type %s) errno=%d\n",
660                                mount_options[i], sb->s_id, name, rc);
661                         goto out;
662                 }
663                 switch (flags[i]) {
664                 case FSCONTEXT_MNT:
665                         fscontext_sid = sid;
666
667                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
668                                         fscontext_sid))
669                                 goto out_double_mount;
670
671                         sbsec->flags |= FSCONTEXT_MNT;
672                         break;
673                 case CONTEXT_MNT:
674                         context_sid = sid;
675
676                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
677                                         context_sid))
678                                 goto out_double_mount;
679
680                         sbsec->flags |= CONTEXT_MNT;
681                         break;
682                 case ROOTCONTEXT_MNT:
683                         rootcontext_sid = sid;
684
685                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
686                                         rootcontext_sid))
687                                 goto out_double_mount;
688
689                         sbsec->flags |= ROOTCONTEXT_MNT;
690
691                         break;
692                 case DEFCONTEXT_MNT:
693                         defcontext_sid = sid;
694
695                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
696                                         defcontext_sid))
697                                 goto out_double_mount;
698
699                         sbsec->flags |= DEFCONTEXT_MNT;
700
701                         break;
702                 default:
703                         rc = -EINVAL;
704                         goto out;
705                 }
706         }
707
708         if (sbsec->flags & SE_SBINITIALIZED) {
709                 /* previously mounted with options, but not on this attempt? */
710                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
711                         goto out_double_mount;
712                 rc = 0;
713                 goto out;
714         }
715
716         if (strcmp(sb->s_type->name, "proc") == 0)
717                 sbsec->flags |= SE_SBPROC;
718
719         /* Determine the labeling behavior to use for this filesystem type. */
720         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
721         if (rc) {
722                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
723                        __func__, sb->s_type->name, rc);
724                 goto out;
725         }
726
727         /* sets the context of the superblock for the fs being mounted. */
728         if (fscontext_sid) {
729                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
730                 if (rc)
731                         goto out;
732
733                 sbsec->sid = fscontext_sid;
734         }
735
736         /*
737          * Switch to using mount point labeling behavior.
738          * sets the label used on all file below the mountpoint, and will set
739          * the superblock context if not already set.
740          */
741         if (context_sid) {
742                 if (!fscontext_sid) {
743                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
744                                                           cred);
745                         if (rc)
746                                 goto out;
747                         sbsec->sid = context_sid;
748                 } else {
749                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
750                                                              cred);
751                         if (rc)
752                                 goto out;
753                 }
754                 if (!rootcontext_sid)
755                         rootcontext_sid = context_sid;
756
757                 sbsec->mntpoint_sid = context_sid;
758                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
759         }
760
761         if (rootcontext_sid) {
762                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
763                                                      cred);
764                 if (rc)
765                         goto out;
766
767                 root_isec->sid = rootcontext_sid;
768                 root_isec->initialized = 1;
769         }
770
771         if (defcontext_sid) {
772                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
773                         rc = -EINVAL;
774                         printk(KERN_WARNING "SELinux: defcontext option is "
775                                "invalid for this filesystem type\n");
776                         goto out;
777                 }
778
779                 if (defcontext_sid != sbsec->def_sid) {
780                         rc = may_context_mount_inode_relabel(defcontext_sid,
781                                                              sbsec, cred);
782                         if (rc)
783                                 goto out;
784                 }
785
786                 sbsec->def_sid = defcontext_sid;
787         }
788
789         rc = sb_finish_set_opts(sb);
790 out:
791         mutex_unlock(&sbsec->lock);
792         return rc;
793 out_double_mount:
794         rc = -EINVAL;
795         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
796                "security settings for (dev %s, type %s)\n", sb->s_id, name);
797         goto out;
798 }
799
800 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
801                                         struct super_block *newsb)
802 {
803         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
804         struct superblock_security_struct *newsbsec = newsb->s_security;
805
806         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
807         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
808         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
809
810         /*
811          * if the parent was able to be mounted it clearly had no special lsm
812          * mount options.  thus we can safely put this sb on the list and deal
813          * with it later
814          */
815         if (!ss_initialized) {
816                 spin_lock(&sb_security_lock);
817                 if (list_empty(&newsbsec->list))
818                         list_add(&newsbsec->list, &superblock_security_head);
819                 spin_unlock(&sb_security_lock);
820                 return;
821         }
822
823         /* how can we clone if the old one wasn't set up?? */
824         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
825
826         /* if fs is reusing a sb, just let its options stand... */
827         if (newsbsec->flags & SE_SBINITIALIZED)
828                 return;
829
830         mutex_lock(&newsbsec->lock);
831
832         newsbsec->flags = oldsbsec->flags;
833
834         newsbsec->sid = oldsbsec->sid;
835         newsbsec->def_sid = oldsbsec->def_sid;
836         newsbsec->behavior = oldsbsec->behavior;
837
838         if (set_context) {
839                 u32 sid = oldsbsec->mntpoint_sid;
840
841                 if (!set_fscontext)
842                         newsbsec->sid = sid;
843                 if (!set_rootcontext) {
844                         struct inode *newinode = newsb->s_root->d_inode;
845                         struct inode_security_struct *newisec = newinode->i_security;
846                         newisec->sid = sid;
847                 }
848                 newsbsec->mntpoint_sid = sid;
849         }
850         if (set_rootcontext) {
851                 const struct inode *oldinode = oldsb->s_root->d_inode;
852                 const struct inode_security_struct *oldisec = oldinode->i_security;
853                 struct inode *newinode = newsb->s_root->d_inode;
854                 struct inode_security_struct *newisec = newinode->i_security;
855
856                 newisec->sid = oldisec->sid;
857         }
858
859         sb_finish_set_opts(newsb);
860         mutex_unlock(&newsbsec->lock);
861 }
862
863 static int selinux_parse_opts_str(char *options,
864                                   struct security_mnt_opts *opts)
865 {
866         char *p;
867         char *context = NULL, *defcontext = NULL;
868         char *fscontext = NULL, *rootcontext = NULL;
869         int rc, num_mnt_opts = 0;
870
871         opts->num_mnt_opts = 0;
872
873         /* Standard string-based options. */
874         while ((p = strsep(&options, "|")) != NULL) {
875                 int token;
876                 substring_t args[MAX_OPT_ARGS];
877
878                 if (!*p)
879                         continue;
880
881                 token = match_token(p, tokens, args);
882
883                 switch (token) {
884                 case Opt_context:
885                         if (context || defcontext) {
886                                 rc = -EINVAL;
887                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
888                                 goto out_err;
889                         }
890                         context = match_strdup(&args[0]);
891                         if (!context) {
892                                 rc = -ENOMEM;
893                                 goto out_err;
894                         }
895                         break;
896
897                 case Opt_fscontext:
898                         if (fscontext) {
899                                 rc = -EINVAL;
900                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
901                                 goto out_err;
902                         }
903                         fscontext = match_strdup(&args[0]);
904                         if (!fscontext) {
905                                 rc = -ENOMEM;
906                                 goto out_err;
907                         }
908                         break;
909
910                 case Opt_rootcontext:
911                         if (rootcontext) {
912                                 rc = -EINVAL;
913                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
914                                 goto out_err;
915                         }
916                         rootcontext = match_strdup(&args[0]);
917                         if (!rootcontext) {
918                                 rc = -ENOMEM;
919                                 goto out_err;
920                         }
921                         break;
922
923                 case Opt_defcontext:
924                         if (context || defcontext) {
925                                 rc = -EINVAL;
926                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
927                                 goto out_err;
928                         }
929                         defcontext = match_strdup(&args[0]);
930                         if (!defcontext) {
931                                 rc = -ENOMEM;
932                                 goto out_err;
933                         }
934                         break;
935                 case Opt_labelsupport:
936                         break;
937                 default:
938                         rc = -EINVAL;
939                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
940                         goto out_err;
941
942                 }
943         }
944
945         rc = -ENOMEM;
946         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
947         if (!opts->mnt_opts)
948                 goto out_err;
949
950         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
951         if (!opts->mnt_opts_flags) {
952                 kfree(opts->mnt_opts);
953                 goto out_err;
954         }
955
956         if (fscontext) {
957                 opts->mnt_opts[num_mnt_opts] = fscontext;
958                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
959         }
960         if (context) {
961                 opts->mnt_opts[num_mnt_opts] = context;
962                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
963         }
964         if (rootcontext) {
965                 opts->mnt_opts[num_mnt_opts] = rootcontext;
966                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
967         }
968         if (defcontext) {
969                 opts->mnt_opts[num_mnt_opts] = defcontext;
970                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
971         }
972
973         opts->num_mnt_opts = num_mnt_opts;
974         return 0;
975
976 out_err:
977         kfree(context);
978         kfree(defcontext);
979         kfree(fscontext);
980         kfree(rootcontext);
981         return rc;
982 }
983 /*
984  * string mount options parsing and call set the sbsec
985  */
986 static int superblock_doinit(struct super_block *sb, void *data)
987 {
988         int rc = 0;
989         char *options = data;
990         struct security_mnt_opts opts;
991
992         security_init_mnt_opts(&opts);
993
994         if (!data)
995                 goto out;
996
997         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
998
999         rc = selinux_parse_opts_str(options, &opts);
1000         if (rc)
1001                 goto out_err;
1002
1003 out:
1004         rc = selinux_set_mnt_opts(sb, &opts);
1005
1006 out_err:
1007         security_free_mnt_opts(&opts);
1008         return rc;
1009 }
1010
1011 static void selinux_write_opts(struct seq_file *m,
1012                                struct security_mnt_opts *opts)
1013 {
1014         int i;
1015         char *prefix;
1016
1017         for (i = 0; i < opts->num_mnt_opts; i++) {
1018                 char *has_comma;
1019
1020                 if (opts->mnt_opts[i])
1021                         has_comma = strchr(opts->mnt_opts[i], ',');
1022                 else
1023                         has_comma = NULL;
1024
1025                 switch (opts->mnt_opts_flags[i]) {
1026                 case CONTEXT_MNT:
1027                         prefix = CONTEXT_STR;
1028                         break;
1029                 case FSCONTEXT_MNT:
1030                         prefix = FSCONTEXT_STR;
1031                         break;
1032                 case ROOTCONTEXT_MNT:
1033                         prefix = ROOTCONTEXT_STR;
1034                         break;
1035                 case DEFCONTEXT_MNT:
1036                         prefix = DEFCONTEXT_STR;
1037                         break;
1038                 case SE_SBLABELSUPP:
1039                         seq_putc(m, ',');
1040                         seq_puts(m, LABELSUPP_STR);
1041                         continue;
1042                 default:
1043                         BUG();
1044                 };
1045                 /* we need a comma before each option */
1046                 seq_putc(m, ',');
1047                 seq_puts(m, prefix);
1048                 if (has_comma)
1049                         seq_putc(m, '\"');
1050                 seq_puts(m, opts->mnt_opts[i]);
1051                 if (has_comma)
1052                         seq_putc(m, '\"');
1053         }
1054 }
1055
1056 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1057 {
1058         struct security_mnt_opts opts;
1059         int rc;
1060
1061         rc = selinux_get_mnt_opts(sb, &opts);
1062         if (rc) {
1063                 /* before policy load we may get EINVAL, don't show anything */
1064                 if (rc == -EINVAL)
1065                         rc = 0;
1066                 return rc;
1067         }
1068
1069         selinux_write_opts(m, &opts);
1070
1071         security_free_mnt_opts(&opts);
1072
1073         return rc;
1074 }
1075
1076 static inline u16 inode_mode_to_security_class(umode_t mode)
1077 {
1078         switch (mode & S_IFMT) {
1079         case S_IFSOCK:
1080                 return SECCLASS_SOCK_FILE;
1081         case S_IFLNK:
1082                 return SECCLASS_LNK_FILE;
1083         case S_IFREG:
1084                 return SECCLASS_FILE;
1085         case S_IFBLK:
1086                 return SECCLASS_BLK_FILE;
1087         case S_IFDIR:
1088                 return SECCLASS_DIR;
1089         case S_IFCHR:
1090                 return SECCLASS_CHR_FILE;
1091         case S_IFIFO:
1092                 return SECCLASS_FIFO_FILE;
1093
1094         }
1095
1096         return SECCLASS_FILE;
1097 }
1098
1099 static inline int default_protocol_stream(int protocol)
1100 {
1101         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1102 }
1103
1104 static inline int default_protocol_dgram(int protocol)
1105 {
1106         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1107 }
1108
1109 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1110 {
1111         switch (family) {
1112         case PF_UNIX:
1113                 switch (type) {
1114                 case SOCK_STREAM:
1115                 case SOCK_SEQPACKET:
1116                         return SECCLASS_UNIX_STREAM_SOCKET;
1117                 case SOCK_DGRAM:
1118                         return SECCLASS_UNIX_DGRAM_SOCKET;
1119                 }
1120                 break;
1121         case PF_INET:
1122         case PF_INET6:
1123                 switch (type) {
1124                 case SOCK_STREAM:
1125                         if (default_protocol_stream(protocol))
1126                                 return SECCLASS_TCP_SOCKET;
1127                         else
1128                                 return SECCLASS_RAWIP_SOCKET;
1129                 case SOCK_DGRAM:
1130                         if (default_protocol_dgram(protocol))
1131                                 return SECCLASS_UDP_SOCKET;
1132                         else
1133                                 return SECCLASS_RAWIP_SOCKET;
1134                 case SOCK_DCCP:
1135                         return SECCLASS_DCCP_SOCKET;
1136                 default:
1137                         return SECCLASS_RAWIP_SOCKET;
1138                 }
1139                 break;
1140         case PF_NETLINK:
1141                 switch (protocol) {
1142                 case NETLINK_ROUTE:
1143                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1144                 case NETLINK_FIREWALL:
1145                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1146                 case NETLINK_INET_DIAG:
1147                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1148                 case NETLINK_NFLOG:
1149                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1150                 case NETLINK_XFRM:
1151                         return SECCLASS_NETLINK_XFRM_SOCKET;
1152                 case NETLINK_SELINUX:
1153                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1154                 case NETLINK_AUDIT:
1155                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1156                 case NETLINK_IP6_FW:
1157                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1158                 case NETLINK_DNRTMSG:
1159                         return SECCLASS_NETLINK_DNRT_SOCKET;
1160                 case NETLINK_KOBJECT_UEVENT:
1161                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1162                 default:
1163                         return SECCLASS_NETLINK_SOCKET;
1164                 }
1165         case PF_PACKET:
1166                 return SECCLASS_PACKET_SOCKET;
1167         case PF_KEY:
1168                 return SECCLASS_KEY_SOCKET;
1169         case PF_APPLETALK:
1170                 return SECCLASS_APPLETALK_SOCKET;
1171         }
1172
1173         return SECCLASS_SOCKET;
1174 }
1175
1176 #ifdef CONFIG_PROC_FS
1177 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1178                                 u16 tclass,
1179                                 u32 *sid)
1180 {
1181         int buflen, rc;
1182         char *buffer, *path, *end;
1183
1184         buffer = (char *)__get_free_page(GFP_KERNEL);
1185         if (!buffer)
1186                 return -ENOMEM;
1187
1188         buflen = PAGE_SIZE;
1189         end = buffer+buflen;
1190         *--end = '\0';
1191         buflen--;
1192         path = end-1;
1193         *path = '/';
1194         while (de && de != de->parent) {
1195                 buflen -= de->namelen + 1;
1196                 if (buflen < 0)
1197                         break;
1198                 end -= de->namelen;
1199                 memcpy(end, de->name, de->namelen);
1200                 *--end = '/';
1201                 path = end;
1202                 de = de->parent;
1203         }
1204         rc = security_genfs_sid("proc", path, tclass, sid);
1205         free_page((unsigned long)buffer);
1206         return rc;
1207 }
1208 #else
1209 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1210                                 u16 tclass,
1211                                 u32 *sid)
1212 {
1213         return -EINVAL;
1214 }
1215 #endif
1216
1217 /* The inode's security attributes must be initialized before first use. */
1218 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1219 {
1220         struct superblock_security_struct *sbsec = NULL;
1221         struct inode_security_struct *isec = inode->i_security;
1222         u32 sid;
1223         struct dentry *dentry;
1224 #define INITCONTEXTLEN 255
1225         char *context = NULL;
1226         unsigned len = 0;
1227         int rc = 0;
1228
1229         if (isec->initialized)
1230                 goto out;
1231
1232         mutex_lock(&isec->lock);
1233         if (isec->initialized)
1234                 goto out_unlock;
1235
1236         sbsec = inode->i_sb->s_security;
1237         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1238                 /* Defer initialization until selinux_complete_init,
1239                    after the initial policy is loaded and the security
1240                    server is ready to handle calls. */
1241                 spin_lock(&sbsec->isec_lock);
1242                 if (list_empty(&isec->list))
1243                         list_add(&isec->list, &sbsec->isec_head);
1244                 spin_unlock(&sbsec->isec_lock);
1245                 goto out_unlock;
1246         }
1247
1248         switch (sbsec->behavior) {
1249         case SECURITY_FS_USE_XATTR:
1250                 if (!inode->i_op->getxattr) {
1251                         isec->sid = sbsec->def_sid;
1252                         break;
1253                 }
1254
1255                 /* Need a dentry, since the xattr API requires one.
1256                    Life would be simpler if we could just pass the inode. */
1257                 if (opt_dentry) {
1258                         /* Called from d_instantiate or d_splice_alias. */
1259                         dentry = dget(opt_dentry);
1260                 } else {
1261                         /* Called from selinux_complete_init, try to find a dentry. */
1262                         dentry = d_find_alias(inode);
1263                 }
1264                 if (!dentry) {
1265                         /*
1266                          * this is can be hit on boot when a file is accessed
1267                          * before the policy is loaded.  When we load policy we
1268                          * may find inodes that have no dentry on the
1269                          * sbsec->isec_head list.  No reason to complain as these
1270                          * will get fixed up the next time we go through
1271                          * inode_doinit with a dentry, before these inodes could
1272                          * be used again by userspace.
1273                          */
1274                         goto out_unlock;
1275                 }
1276
1277                 len = INITCONTEXTLEN;
1278                 context = kmalloc(len+1, GFP_NOFS);
1279                 if (!context) {
1280                         rc = -ENOMEM;
1281                         dput(dentry);
1282                         goto out_unlock;
1283                 }
1284                 context[len] = '\0';
1285                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1286                                            context, len);
1287                 if (rc == -ERANGE) {
1288                         /* Need a larger buffer.  Query for the right size. */
1289                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1290                                                    NULL, 0);
1291                         if (rc < 0) {
1292                                 dput(dentry);
1293                                 goto out_unlock;
1294                         }
1295                         kfree(context);
1296                         len = rc;
1297                         context = kmalloc(len+1, GFP_NOFS);
1298                         if (!context) {
1299                                 rc = -ENOMEM;
1300                                 dput(dentry);
1301                                 goto out_unlock;
1302                         }
1303                         context[len] = '\0';
1304                         rc = inode->i_op->getxattr(dentry,
1305                                                    XATTR_NAME_SELINUX,
1306                                                    context, len);
1307                 }
1308                 dput(dentry);
1309                 if (rc < 0) {
1310                         if (rc != -ENODATA) {
1311                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1312                                        "%d for dev=%s ino=%ld\n", __func__,
1313                                        -rc, inode->i_sb->s_id, inode->i_ino);
1314                                 kfree(context);
1315                                 goto out_unlock;
1316                         }
1317                         /* Map ENODATA to the default file SID */
1318                         sid = sbsec->def_sid;
1319                         rc = 0;
1320                 } else {
1321                         rc = security_context_to_sid_default(context, rc, &sid,
1322                                                              sbsec->def_sid,
1323                                                              GFP_NOFS);
1324                         if (rc) {
1325                                 char *dev = inode->i_sb->s_id;
1326                                 unsigned long ino = inode->i_ino;
1327
1328                                 if (rc == -EINVAL) {
1329                                         if (printk_ratelimit())
1330                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1331                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1332                                                         "filesystem in question.\n", ino, dev, context);
1333                                 } else {
1334                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1335                                                "returned %d for dev=%s ino=%ld\n",
1336                                                __func__, context, -rc, dev, ino);
1337                                 }
1338                                 kfree(context);
1339                                 /* Leave with the unlabeled SID */
1340                                 rc = 0;
1341                                 break;
1342                         }
1343                 }
1344                 kfree(context);
1345                 isec->sid = sid;
1346                 break;
1347         case SECURITY_FS_USE_TASK:
1348                 isec->sid = isec->task_sid;
1349                 break;
1350         case SECURITY_FS_USE_TRANS:
1351                 /* Default to the fs SID. */
1352                 isec->sid = sbsec->sid;
1353
1354                 /* Try to obtain a transition SID. */
1355                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1356                 rc = security_transition_sid(isec->task_sid,
1357                                              sbsec->sid,
1358                                              isec->sclass,
1359                                              &sid);
1360                 if (rc)
1361                         goto out_unlock;
1362                 isec->sid = sid;
1363                 break;
1364         case SECURITY_FS_USE_MNTPOINT:
1365                 isec->sid = sbsec->mntpoint_sid;
1366                 break;
1367         default:
1368                 /* Default to the fs superblock SID. */
1369                 isec->sid = sbsec->sid;
1370
1371                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1372                         struct proc_inode *proci = PROC_I(inode);
1373                         if (proci->pde) {
1374                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1375                                 rc = selinux_proc_get_sid(proci->pde,
1376                                                           isec->sclass,
1377                                                           &sid);
1378                                 if (rc)
1379                                         goto out_unlock;
1380                                 isec->sid = sid;
1381                         }
1382                 }
1383                 break;
1384         }
1385
1386         isec->initialized = 1;
1387
1388 out_unlock:
1389         mutex_unlock(&isec->lock);
1390 out:
1391         if (isec->sclass == SECCLASS_FILE)
1392                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1393         return rc;
1394 }
1395
1396 /* Convert a Linux signal to an access vector. */
1397 static inline u32 signal_to_av(int sig)
1398 {
1399         u32 perm = 0;
1400
1401         switch (sig) {
1402         case SIGCHLD:
1403                 /* Commonly granted from child to parent. */
1404                 perm = PROCESS__SIGCHLD;
1405                 break;
1406         case SIGKILL:
1407                 /* Cannot be caught or ignored */
1408                 perm = PROCESS__SIGKILL;
1409                 break;
1410         case SIGSTOP:
1411                 /* Cannot be caught or ignored */
1412                 perm = PROCESS__SIGSTOP;
1413                 break;
1414         default:
1415                 /* All other signals. */
1416                 perm = PROCESS__SIGNAL;
1417                 break;
1418         }
1419
1420         return perm;
1421 }
1422
1423 /*
1424  * Check permission between a pair of credentials
1425  * fork check, ptrace check, etc.
1426  */
1427 static int cred_has_perm(const struct cred *actor,
1428                          const struct cred *target,
1429                          u32 perms)
1430 {
1431         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1432
1433         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1434 }
1435
1436 /*
1437  * Check permission between a pair of tasks, e.g. signal checks,
1438  * fork check, ptrace check, etc.
1439  * tsk1 is the actor and tsk2 is the target
1440  * - this uses the default subjective creds of tsk1
1441  */
1442 static int task_has_perm(const struct task_struct *tsk1,
1443                          const struct task_struct *tsk2,
1444                          u32 perms)
1445 {
1446         const struct task_security_struct *__tsec1, *__tsec2;
1447         u32 sid1, sid2;
1448
1449         rcu_read_lock();
1450         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1451         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1452         rcu_read_unlock();
1453         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1454 }
1455
1456 /*
1457  * Check permission between current and another task, e.g. signal checks,
1458  * fork check, ptrace check, etc.
1459  * current is the actor and tsk2 is the target
1460  * - this uses current's subjective creds
1461  */
1462 static int current_has_perm(const struct task_struct *tsk,
1463                             u32 perms)
1464 {
1465         u32 sid, tsid;
1466
1467         sid = current_sid();
1468         tsid = task_sid(tsk);
1469         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1470 }
1471
1472 #if CAP_LAST_CAP > 63
1473 #error Fix SELinux to handle capabilities > 63.
1474 #endif
1475
1476 /* Check whether a task is allowed to use a capability. */
1477 static int task_has_capability(struct task_struct *tsk,
1478                                const struct cred *cred,
1479                                int cap, int audit)
1480 {
1481         struct avc_audit_data ad;
1482         struct av_decision avd;
1483         u16 sclass;
1484         u32 sid = cred_sid(cred);
1485         u32 av = CAP_TO_MASK(cap);
1486         int rc;
1487
1488         AVC_AUDIT_DATA_INIT(&ad, CAP);
1489         ad.tsk = tsk;
1490         ad.u.cap = cap;
1491
1492         switch (CAP_TO_INDEX(cap)) {
1493         case 0:
1494                 sclass = SECCLASS_CAPABILITY;
1495                 break;
1496         case 1:
1497                 sclass = SECCLASS_CAPABILITY2;
1498                 break;
1499         default:
1500                 printk(KERN_ERR
1501                        "SELinux:  out of range capability %d\n", cap);
1502                 BUG();
1503         }
1504
1505         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1506         if (audit == SECURITY_CAP_AUDIT)
1507                 avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1508         return rc;
1509 }
1510
1511 /* Check whether a task is allowed to use a system operation. */
1512 static int task_has_system(struct task_struct *tsk,
1513                            u32 perms)
1514 {
1515         u32 sid = task_sid(tsk);
1516
1517         return avc_has_perm(sid, SECINITSID_KERNEL,
1518                             SECCLASS_SYSTEM, perms, NULL);
1519 }
1520
1521 /* Check whether a task has a particular permission to an inode.
1522    The 'adp' parameter is optional and allows other audit
1523    data to be passed (e.g. the dentry). */
1524 static int inode_has_perm(const struct cred *cred,
1525                           struct inode *inode,
1526                           u32 perms,
1527                           struct avc_audit_data *adp)
1528 {
1529         struct inode_security_struct *isec;
1530         struct avc_audit_data ad;
1531         u32 sid;
1532
1533         if (unlikely(IS_PRIVATE(inode)))
1534                 return 0;
1535
1536         sid = cred_sid(cred);
1537         isec = inode->i_security;
1538
1539         if (!adp) {
1540                 adp = &ad;
1541                 AVC_AUDIT_DATA_INIT(&ad, FS);
1542                 ad.u.fs.inode = inode;
1543         }
1544
1545         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1546 }
1547
1548 /* Same as inode_has_perm, but pass explicit audit data containing
1549    the dentry to help the auditing code to more easily generate the
1550    pathname if needed. */
1551 static inline int dentry_has_perm(const struct cred *cred,
1552                                   struct vfsmount *mnt,
1553                                   struct dentry *dentry,
1554                                   u32 av)
1555 {
1556         struct inode *inode = dentry->d_inode;
1557         struct avc_audit_data ad;
1558
1559         AVC_AUDIT_DATA_INIT(&ad, FS);
1560         ad.u.fs.path.mnt = mnt;
1561         ad.u.fs.path.dentry = dentry;
1562         return inode_has_perm(cred, inode, av, &ad);
1563 }
1564
1565 /* Check whether a task can use an open file descriptor to
1566    access an inode in a given way.  Check access to the
1567    descriptor itself, and then use dentry_has_perm to
1568    check a particular permission to the file.
1569    Access to the descriptor is implicitly granted if it
1570    has the same SID as the process.  If av is zero, then
1571    access to the file is not checked, e.g. for cases
1572    where only the descriptor is affected like seek. */
1573 static int file_has_perm(const struct cred *cred,
1574                          struct file *file,
1575                          u32 av)
1576 {
1577         struct file_security_struct *fsec = file->f_security;
1578         struct inode *inode = file->f_path.dentry->d_inode;
1579         struct avc_audit_data ad;
1580         u32 sid = cred_sid(cred);
1581         int rc;
1582
1583         AVC_AUDIT_DATA_INIT(&ad, FS);
1584         ad.u.fs.path = file->f_path;
1585
1586         if (sid != fsec->sid) {
1587                 rc = avc_has_perm(sid, fsec->sid,
1588                                   SECCLASS_FD,
1589                                   FD__USE,
1590                                   &ad);
1591                 if (rc)
1592                         goto out;
1593         }
1594
1595         /* av is zero if only checking access to the descriptor. */
1596         rc = 0;
1597         if (av)
1598                 rc = inode_has_perm(cred, inode, av, &ad);
1599
1600 out:
1601         return rc;
1602 }
1603
1604 /* Check whether a task can create a file. */
1605 static int may_create(struct inode *dir,
1606                       struct dentry *dentry,
1607                       u16 tclass)
1608 {
1609         const struct cred *cred = current_cred();
1610         const struct task_security_struct *tsec = cred->security;
1611         struct inode_security_struct *dsec;
1612         struct superblock_security_struct *sbsec;
1613         u32 sid, newsid;
1614         struct avc_audit_data ad;
1615         int rc;
1616
1617         dsec = dir->i_security;
1618         sbsec = dir->i_sb->s_security;
1619
1620         sid = tsec->sid;
1621         newsid = tsec->create_sid;
1622
1623         AVC_AUDIT_DATA_INIT(&ad, FS);
1624         ad.u.fs.path.dentry = dentry;
1625
1626         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1627                           DIR__ADD_NAME | DIR__SEARCH,
1628                           &ad);
1629         if (rc)
1630                 return rc;
1631
1632         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1633                 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
1634                 if (rc)
1635                         return rc;
1636         }
1637
1638         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1639         if (rc)
1640                 return rc;
1641
1642         return avc_has_perm(newsid, sbsec->sid,
1643                             SECCLASS_FILESYSTEM,
1644                             FILESYSTEM__ASSOCIATE, &ad);
1645 }
1646
1647 /* Check whether a task can create a key. */
1648 static int may_create_key(u32 ksid,
1649                           struct task_struct *ctx)
1650 {
1651         u32 sid = task_sid(ctx);
1652
1653         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1654 }
1655
1656 #define MAY_LINK        0
1657 #define MAY_UNLINK      1
1658 #define MAY_RMDIR       2
1659
1660 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1661 static int may_link(struct inode *dir,
1662                     struct dentry *dentry,
1663                     int kind)
1664
1665 {
1666         struct inode_security_struct *dsec, *isec;
1667         struct avc_audit_data ad;
1668         u32 sid = current_sid();
1669         u32 av;
1670         int rc;
1671
1672         dsec = dir->i_security;
1673         isec = dentry->d_inode->i_security;
1674
1675         AVC_AUDIT_DATA_INIT(&ad, FS);
1676         ad.u.fs.path.dentry = dentry;
1677
1678         av = DIR__SEARCH;
1679         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1680         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1681         if (rc)
1682                 return rc;
1683
1684         switch (kind) {
1685         case MAY_LINK:
1686                 av = FILE__LINK;
1687                 break;
1688         case MAY_UNLINK:
1689                 av = FILE__UNLINK;
1690                 break;
1691         case MAY_RMDIR:
1692                 av = DIR__RMDIR;
1693                 break;
1694         default:
1695                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1696                         __func__, kind);
1697                 return 0;
1698         }
1699
1700         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1701         return rc;
1702 }
1703
1704 static inline int may_rename(struct inode *old_dir,
1705                              struct dentry *old_dentry,
1706                              struct inode *new_dir,
1707                              struct dentry *new_dentry)
1708 {
1709         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1710         struct avc_audit_data ad;
1711         u32 sid = current_sid();
1712         u32 av;
1713         int old_is_dir, new_is_dir;
1714         int rc;
1715
1716         old_dsec = old_dir->i_security;
1717         old_isec = old_dentry->d_inode->i_security;
1718         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1719         new_dsec = new_dir->i_security;
1720
1721         AVC_AUDIT_DATA_INIT(&ad, FS);
1722
1723         ad.u.fs.path.dentry = old_dentry;
1724         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1725                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1726         if (rc)
1727                 return rc;
1728         rc = avc_has_perm(sid, old_isec->sid,
1729                           old_isec->sclass, FILE__RENAME, &ad);
1730         if (rc)
1731                 return rc;
1732         if (old_is_dir && new_dir != old_dir) {
1733                 rc = avc_has_perm(sid, old_isec->sid,
1734                                   old_isec->sclass, DIR__REPARENT, &ad);
1735                 if (rc)
1736                         return rc;
1737         }
1738
1739         ad.u.fs.path.dentry = new_dentry;
1740         av = DIR__ADD_NAME | DIR__SEARCH;
1741         if (new_dentry->d_inode)
1742                 av |= DIR__REMOVE_NAME;
1743         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1744         if (rc)
1745                 return rc;
1746         if (new_dentry->d_inode) {
1747                 new_isec = new_dentry->d_inode->i_security;
1748                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1749                 rc = avc_has_perm(sid, new_isec->sid,
1750                                   new_isec->sclass,
1751                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1752                 if (rc)
1753                         return rc;
1754         }
1755
1756         return 0;
1757 }
1758
1759 /* Check whether a task can perform a filesystem operation. */
1760 static int superblock_has_perm(const struct cred *cred,
1761                                struct super_block *sb,
1762                                u32 perms,
1763                                struct avc_audit_data *ad)
1764 {
1765         struct superblock_security_struct *sbsec;
1766         u32 sid = cred_sid(cred);
1767
1768         sbsec = sb->s_security;
1769         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1770 }
1771
1772 /* Convert a Linux mode and permission mask to an access vector. */
1773 static inline u32 file_mask_to_av(int mode, int mask)
1774 {
1775         u32 av = 0;
1776
1777         if ((mode & S_IFMT) != S_IFDIR) {
1778                 if (mask & MAY_EXEC)
1779                         av |= FILE__EXECUTE;
1780                 if (mask & MAY_READ)
1781                         av |= FILE__READ;
1782
1783                 if (mask & MAY_APPEND)
1784                         av |= FILE__APPEND;
1785                 else if (mask & MAY_WRITE)
1786                         av |= FILE__WRITE;
1787
1788         } else {
1789                 if (mask & MAY_EXEC)
1790                         av |= DIR__SEARCH;
1791                 if (mask & MAY_WRITE)
1792                         av |= DIR__WRITE;
1793                 if (mask & MAY_READ)
1794                         av |= DIR__READ;
1795         }
1796
1797         return av;
1798 }
1799
1800 /* Convert a Linux file to an access vector. */
1801 static inline u32 file_to_av(struct file *file)
1802 {
1803         u32 av = 0;
1804
1805         if (file->f_mode & FMODE_READ)
1806                 av |= FILE__READ;
1807         if (file->f_mode & FMODE_WRITE) {
1808                 if (file->f_flags & O_APPEND)
1809                         av |= FILE__APPEND;
1810                 else
1811                         av |= FILE__WRITE;
1812         }
1813         if (!av) {
1814                 /*
1815                  * Special file opened with flags 3 for ioctl-only use.
1816                  */
1817                 av = FILE__IOCTL;
1818         }
1819
1820         return av;
1821 }
1822
1823 /*
1824  * Convert a file to an access vector and include the correct open
1825  * open permission.
1826  */
1827 static inline u32 open_file_to_av(struct file *file)
1828 {
1829         u32 av = file_to_av(file);
1830
1831         if (selinux_policycap_openperm) {
1832                 mode_t mode = file->f_path.dentry->d_inode->i_mode;
1833                 /*
1834                  * lnk files and socks do not really have an 'open'
1835                  */
1836                 if (S_ISREG(mode))
1837                         av |= FILE__OPEN;
1838                 else if (S_ISCHR(mode))
1839                         av |= CHR_FILE__OPEN;
1840                 else if (S_ISBLK(mode))
1841                         av |= BLK_FILE__OPEN;
1842                 else if (S_ISFIFO(mode))
1843                         av |= FIFO_FILE__OPEN;
1844                 else if (S_ISDIR(mode))
1845                         av |= DIR__OPEN;
1846                 else if (S_ISSOCK(mode))
1847                         av |= SOCK_FILE__OPEN;
1848                 else
1849                         printk(KERN_ERR "SELinux: WARNING: inside %s with "
1850                                 "unknown mode:%o\n", __func__, mode);
1851         }
1852         return av;
1853 }
1854
1855 /* Hook functions begin here. */
1856
1857 static int selinux_ptrace_may_access(struct task_struct *child,
1858                                      unsigned int mode)
1859 {
1860         int rc;
1861
1862         rc = cap_ptrace_may_access(child, mode);
1863         if (rc)
1864                 return rc;
1865
1866         if (mode == PTRACE_MODE_READ) {
1867                 u32 sid = current_sid();
1868                 u32 csid = task_sid(child);
1869                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1870         }
1871
1872         return current_has_perm(child, PROCESS__PTRACE);
1873 }
1874
1875 static int selinux_ptrace_traceme(struct task_struct *parent)
1876 {
1877         int rc;
1878
1879         rc = cap_ptrace_traceme(parent);
1880         if (rc)
1881                 return rc;
1882
1883         return task_has_perm(parent, current, PROCESS__PTRACE);
1884 }
1885
1886 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1887                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1888 {
1889         int error;
1890
1891         error = current_has_perm(target, PROCESS__GETCAP);
1892         if (error)
1893                 return error;
1894
1895         return cap_capget(target, effective, inheritable, permitted);
1896 }
1897
1898 static int selinux_capset(struct cred *new, const struct cred *old,
1899                           const kernel_cap_t *effective,
1900                           const kernel_cap_t *inheritable,
1901                           const kernel_cap_t *permitted)
1902 {
1903         int error;
1904
1905         error = cap_capset(new, old,
1906                                       effective, inheritable, permitted);
1907         if (error)
1908                 return error;
1909
1910         return cred_has_perm(old, new, PROCESS__SETCAP);
1911 }
1912
1913 /*
1914  * (This comment used to live with the selinux_task_setuid hook,
1915  * which was removed).
1916  *
1917  * Since setuid only affects the current process, and since the SELinux
1918  * controls are not based on the Linux identity attributes, SELinux does not
1919  * need to control this operation.  However, SELinux does control the use of
1920  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1921  */
1922
1923 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1924                            int cap, int audit)
1925 {
1926         int rc;
1927
1928         rc = cap_capable(tsk, cred, cap, audit);
1929         if (rc)
1930                 return rc;
1931
1932         return task_has_capability(tsk, cred, cap, audit);
1933 }
1934
1935 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1936 {
1937         int buflen, rc;
1938         char *buffer, *path, *end;
1939
1940         rc = -ENOMEM;
1941         buffer = (char *)__get_free_page(GFP_KERNEL);
1942         if (!buffer)
1943                 goto out;
1944
1945         buflen = PAGE_SIZE;
1946         end = buffer+buflen;
1947         *--end = '\0';
1948         buflen--;
1949         path = end-1;
1950         *path = '/';
1951         while (table) {
1952                 const char *name = table->procname;
1953                 size_t namelen = strlen(name);
1954                 buflen -= namelen + 1;
1955                 if (buflen < 0)
1956                         goto out_free;
1957                 end -= namelen;
1958                 memcpy(end, name, namelen);
1959                 *--end = '/';
1960                 path = end;
1961                 table = table->parent;
1962         }
1963         buflen -= 4;
1964         if (buflen < 0)
1965                 goto out_free;
1966         end -= 4;
1967         memcpy(end, "/sys", 4);
1968         path = end;
1969         rc = security_genfs_sid("proc", path, tclass, sid);
1970 out_free:
1971         free_page((unsigned long)buffer);
1972 out:
1973         return rc;
1974 }
1975
1976 static int selinux_sysctl(ctl_table *table, int op)
1977 {
1978         int error = 0;
1979         u32 av;
1980         u32 tsid, sid;
1981         int rc;
1982
1983         sid = current_sid();
1984
1985         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1986                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1987         if (rc) {
1988                 /* Default to the well-defined sysctl SID. */
1989                 tsid = SECINITSID_SYSCTL;
1990         }
1991
1992         /* The op values are "defined" in sysctl.c, thereby creating
1993          * a bad coupling between this module and sysctl.c */
1994         if (op == 001) {
1995                 error = avc_has_perm(sid, tsid,
1996                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1997         } else {
1998                 av = 0;
1999                 if (op & 004)
2000                         av |= FILE__READ;
2001                 if (op & 002)
2002                         av |= FILE__WRITE;
2003                 if (av)
2004                         error = avc_has_perm(sid, tsid,
2005                                              SECCLASS_FILE, av, NULL);
2006         }
2007
2008         return error;
2009 }
2010
2011 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2012 {
2013         const struct cred *cred = current_cred();
2014         int rc = 0;
2015
2016         if (!sb)
2017                 return 0;
2018
2019         switch (cmds) {
2020         case Q_SYNC:
2021         case Q_QUOTAON:
2022         case Q_QUOTAOFF:
2023         case Q_SETINFO:
2024         case Q_SETQUOTA:
2025                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2026                 break;
2027         case Q_GETFMT:
2028         case Q_GETINFO:
2029         case Q_GETQUOTA:
2030                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2031                 break;
2032         default:
2033                 rc = 0;  /* let the kernel handle invalid cmds */
2034                 break;
2035         }
2036         return rc;
2037 }
2038
2039 static int selinux_quota_on(struct dentry *dentry)
2040 {
2041         const struct cred *cred = current_cred();
2042
2043         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
2044 }
2045
2046 static int selinux_syslog(int type)
2047 {
2048         int rc;
2049
2050         rc = cap_syslog(type);
2051         if (rc)
2052                 return rc;
2053
2054         switch (type) {
2055         case 3:         /* Read last kernel messages */
2056         case 10:        /* Return size of the log buffer */
2057                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2058                 break;
2059         case 6:         /* Disable logging to console */
2060         case 7:         /* Enable logging to console */
2061         case 8:         /* Set level of messages printed to console */
2062                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2063                 break;
2064         case 0:         /* Close log */
2065         case 1:         /* Open log */
2066         case 2:         /* Read from log */
2067         case 4:         /* Read/clear last kernel messages */
2068         case 5:         /* Clear ring buffer */
2069         default:
2070                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2071                 break;
2072         }
2073         return rc;
2074 }
2075
2076 /*
2077  * Check that a process has enough memory to allocate a new virtual
2078  * mapping. 0 means there is enough memory for the allocation to
2079  * succeed and -ENOMEM implies there is not.
2080  *
2081  * Do not audit the selinux permission check, as this is applied to all
2082  * processes that allocate mappings.
2083  */
2084 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2085 {
2086         int rc, cap_sys_admin = 0;
2087
2088         rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2089                              SECURITY_CAP_NOAUDIT);
2090         if (rc == 0)
2091                 cap_sys_admin = 1;
2092
2093         return __vm_enough_memory(mm, pages, cap_sys_admin);
2094 }
2095
2096 /* binprm security operations */
2097
2098 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2099 {
2100         const struct task_security_struct *old_tsec;
2101         struct task_security_struct *new_tsec;
2102         struct inode_security_struct *isec;
2103         struct avc_audit_data ad;
2104         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2105         int rc;
2106
2107         rc = cap_bprm_set_creds(bprm);
2108         if (rc)
2109                 return rc;
2110
2111         /* SELinux context only depends on initial program or script and not
2112          * the script interpreter */
2113         if (bprm->cred_prepared)
2114                 return 0;
2115
2116         old_tsec = current_security();
2117         new_tsec = bprm->cred->security;
2118         isec = inode->i_security;
2119
2120         /* Default to the current task SID. */
2121         new_tsec->sid = old_tsec->sid;
2122         new_tsec->osid = old_tsec->sid;
2123
2124         /* Reset fs, key, and sock SIDs on execve. */
2125         new_tsec->create_sid = 0;
2126         new_tsec->keycreate_sid = 0;
2127         new_tsec->sockcreate_sid = 0;
2128
2129         if (old_tsec->exec_sid) {
2130                 new_tsec->sid = old_tsec->exec_sid;
2131                 /* Reset exec SID on execve. */
2132                 new_tsec->exec_sid = 0;
2133         } else {
2134                 /* Check for a default transition on this program. */
2135                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2136                                              SECCLASS_PROCESS, &new_tsec->sid);
2137                 if (rc)
2138                         return rc;
2139         }
2140
2141         AVC_AUDIT_DATA_INIT(&ad, FS);
2142         ad.u.fs.path = bprm->file->f_path;
2143
2144         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2145                 new_tsec->sid = old_tsec->sid;
2146
2147         if (new_tsec->sid == old_tsec->sid) {
2148                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2149                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2150                 if (rc)
2151                         return rc;
2152         } else {
2153                 /* Check permissions for the transition. */
2154                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2155                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2156                 if (rc)
2157                         return rc;
2158
2159                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2160                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2161                 if (rc)
2162                         return rc;
2163
2164                 /* Check for shared state */
2165                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2166                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2167                                           SECCLASS_PROCESS, PROCESS__SHARE,
2168                                           NULL);
2169                         if (rc)
2170                                 return -EPERM;
2171                 }
2172
2173                 /* Make sure that anyone attempting to ptrace over a task that
2174                  * changes its SID has the appropriate permit */
2175                 if (bprm->unsafe &
2176                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2177                         struct task_struct *tracer;
2178                         struct task_security_struct *sec;
2179                         u32 ptsid = 0;
2180
2181                         rcu_read_lock();
2182                         tracer = tracehook_tracer_task(current);
2183                         if (likely(tracer != NULL)) {
2184                                 sec = __task_cred(tracer)->security;
2185                                 ptsid = sec->sid;
2186                         }
2187                         rcu_read_unlock();
2188
2189                         if (ptsid != 0) {
2190                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2191                                                   SECCLASS_PROCESS,
2192                                                   PROCESS__PTRACE, NULL);
2193                                 if (rc)
2194                                         return -EPERM;
2195                         }
2196                 }
2197
2198                 /* Clear any possibly unsafe personality bits on exec: */
2199                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2200         }
2201
2202         return 0;
2203 }
2204
2205 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2206 {
2207         const struct cred *cred = current_cred();
2208         const struct task_security_struct *tsec = cred->security;
2209         u32 sid, osid;
2210         int atsecure = 0;
2211
2212         sid = tsec->sid;
2213         osid = tsec->osid;
2214
2215         if (osid != sid) {
2216                 /* Enable secure mode for SIDs transitions unless
2217                    the noatsecure permission is granted between
2218                    the two SIDs, i.e. ahp returns 0. */
2219                 atsecure = avc_has_perm(osid, sid,
2220                                         SECCLASS_PROCESS,
2221                                         PROCESS__NOATSECURE, NULL);
2222         }
2223
2224         return (atsecure || cap_bprm_secureexec(bprm));
2225 }
2226
2227 extern struct vfsmount *selinuxfs_mount;
2228 extern struct dentry *selinux_null;
2229
2230 /* Derived from fs/exec.c:flush_old_files. */
2231 static inline void flush_unauthorized_files(const struct cred *cred,
2232                                             struct files_struct *files)
2233 {
2234         struct avc_audit_data ad;
2235         struct file *file, *devnull = NULL;
2236         struct tty_struct *tty;
2237         struct fdtable *fdt;
2238         long j = -1;
2239         int drop_tty = 0;
2240
2241         tty = get_current_tty();
2242         if (tty) {
2243                 file_list_lock();
2244                 if (!list_empty(&tty->tty_files)) {
2245                         struct inode *inode;
2246
2247                         /* Revalidate access to controlling tty.
2248                            Use inode_has_perm on the tty inode directly rather
2249                            than using file_has_perm, as this particular open
2250                            file may belong to another process and we are only
2251                            interested in the inode-based check here. */
2252                         file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2253                         inode = file->f_path.dentry->d_inode;
2254                         if (inode_has_perm(cred, inode,
2255                                            FILE__READ | FILE__WRITE, NULL)) {
2256                                 drop_tty = 1;
2257                         }
2258                 }
2259                 file_list_unlock();
2260                 tty_kref_put(tty);
2261         }
2262         /* Reset controlling tty. */
2263         if (drop_tty)
2264                 no_tty();
2265
2266         /* Revalidate access to inherited open files. */
2267
2268         AVC_AUDIT_DATA_INIT(&ad, FS);
2269
2270         spin_lock(&files->file_lock);
2271         for (;;) {
2272                 unsigned long set, i;
2273                 int fd;
2274
2275                 j++;
2276                 i = j * __NFDBITS;
2277                 fdt = files_fdtable(files);
2278                 if (i >= fdt->max_fds)
2279                         break;
2280                 set = fdt->open_fds->fds_bits[j];
2281                 if (!set)
2282                         continue;
2283                 spin_unlock(&files->file_lock);
2284                 for ( ; set ; i++, set >>= 1) {
2285                         if (set & 1) {
2286                                 file = fget(i);
2287                                 if (!file)
2288                                         continue;
2289                                 if (file_has_perm(cred,
2290                                                   file,
2291                                                   file_to_av(file))) {
2292                                         sys_close(i);
2293                                         fd = get_unused_fd();
2294                                         if (fd != i) {
2295                                                 if (fd >= 0)
2296                                                         put_unused_fd(fd);
2297                                                 fput(file);
2298                                                 continue;
2299                                         }
2300                                         if (devnull) {
2301                                                 get_file(devnull);
2302                                         } else {
2303                                                 devnull = dentry_open(
2304                                                         dget(selinux_null),
2305                                                         mntget(selinuxfs_mount),
2306                                                         O_RDWR, cred);
2307                                                 if (IS_ERR(devnull)) {
2308                                                         devnull = NULL;
2309                                                         put_unused_fd(fd);
2310                                                         fput(file);
2311                                                         continue;
2312                                                 }
2313                                         }
2314                                         fd_install(fd, devnull);
2315                                 }
2316                                 fput(file);
2317                         }
2318                 }
2319                 spin_lock(&files->file_lock);
2320
2321         }
2322         spin_unlock(&files->file_lock);
2323 }
2324
2325 /*
2326  * Prepare a process for imminent new credential changes due to exec
2327  */
2328 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2329 {
2330         struct task_security_struct *new_tsec;
2331         struct rlimit *rlim, *initrlim;
2332         int rc, i;
2333
2334         new_tsec = bprm->cred->security;
2335         if (new_tsec->sid == new_tsec->osid)
2336                 return;
2337
2338         /* Close files for which the new task SID is not authorized. */
2339         flush_unauthorized_files(bprm->cred, current->files);
2340
2341         /* Always clear parent death signal on SID transitions. */
2342         current->pdeath_signal = 0;
2343
2344         /* Check whether the new SID can inherit resource limits from the old
2345          * SID.  If not, reset all soft limits to the lower of the current
2346          * task's hard limit and the init task's soft limit.
2347          *
2348          * Note that the setting of hard limits (even to lower them) can be
2349          * controlled by the setrlimit check.  The inclusion of the init task's
2350          * soft limit into the computation is to avoid resetting soft limits
2351          * higher than the default soft limit for cases where the default is
2352          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2353          */
2354         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2355                           PROCESS__RLIMITINH, NULL);
2356         if (rc) {
2357                 for (i = 0; i < RLIM_NLIMITS; i++) {
2358                         rlim = current->signal->rlim + i;
2359                         initrlim = init_task.signal->rlim + i;
2360                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2361                 }
2362                 update_rlimit_cpu(rlim->rlim_cur);
2363         }
2364 }
2365
2366 /*
2367  * Clean up the process immediately after the installation of new credentials
2368  * due to exec
2369  */
2370 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2371 {
2372         const struct task_security_struct *tsec = current_security();
2373         struct itimerval itimer;
2374         struct sighand_struct *psig;
2375         u32 osid, sid;
2376         int rc, i;
2377         unsigned long flags;
2378
2379         osid = tsec->osid;
2380         sid = tsec->sid;
2381
2382         if (sid == osid)
2383                 return;
2384
2385         /* Check whether the new SID can inherit signal state from the old SID.
2386          * If not, clear itimers to avoid subsequent signal generation and
2387          * flush and unblock signals.
2388          *
2389          * This must occur _after_ the task SID has been updated so that any
2390          * kill done after the flush will be checked against the new SID.
2391          */
2392         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2393         if (rc) {
2394                 memset(&itimer, 0, sizeof itimer);
2395                 for (i = 0; i < 3; i++)
2396                         do_setitimer(i, &itimer, NULL);
2397                 spin_lock_irq(&current->sighand->siglock);
2398                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2399                         __flush_signals(current);
2400                         flush_signal_handlers(current, 1);
2401                         sigemptyset(&current->blocked);
2402                 }
2403                 spin_unlock_irq(&current->sighand->siglock);
2404         }
2405
2406         /* Wake up the parent if it is waiting so that it can recheck
2407          * wait permission to the new task SID. */
2408         read_lock_irq(&tasklist_lock);
2409         psig = current->parent->sighand;
2410         spin_lock_irqsave(&psig->siglock, flags);
2411         wake_up_interruptible(&current->parent->signal->wait_chldexit);
2412         spin_unlock_irqrestore(&psig->siglock, flags);
2413         read_unlock_irq(&tasklist_lock);
2414 }
2415
2416 /* superblock security operations */
2417
2418 static int selinux_sb_alloc_security(struct super_block *sb)
2419 {
2420         return superblock_alloc_security(sb);
2421 }
2422
2423 static void selinux_sb_free_security(struct super_block *sb)
2424 {
2425         superblock_free_security(sb);
2426 }
2427
2428 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2429 {
2430         if (plen > olen)
2431                 return 0;
2432
2433         return !memcmp(prefix, option, plen);
2434 }
2435
2436 static inline int selinux_option(char *option, int len)
2437 {
2438         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2439                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2440                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2441                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2442                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2443 }
2444
2445 static inline void take_option(char **to, char *from, int *first, int len)
2446 {
2447         if (!*first) {
2448                 **to = ',';
2449                 *to += 1;
2450         } else
2451                 *first = 0;
2452         memcpy(*to, from, len);
2453         *to += len;
2454 }
2455
2456 static inline void take_selinux_option(char **to, char *from, int *first,
2457                                        int len)
2458 {
2459         int current_size = 0;
2460
2461         if (!*first) {
2462                 **to = '|';
2463                 *to += 1;
2464         } else
2465                 *first = 0;
2466
2467         while (current_size < len) {
2468                 if (*from != '"') {
2469                         **to = *from;
2470                         *to += 1;
2471                 }
2472                 from += 1;
2473                 current_size += 1;
2474         }
2475 }
2476
2477 static int selinux_sb_copy_data(char *orig, char *copy)
2478 {
2479         int fnosec, fsec, rc = 0;
2480         char *in_save, *in_curr, *in_end;
2481         char *sec_curr, *nosec_save, *nosec;
2482         int open_quote = 0;
2483
2484         in_curr = orig;
2485         sec_curr = copy;
2486
2487         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2488         if (!nosec) {
2489                 rc = -ENOMEM;
2490                 goto out;
2491         }
2492
2493         nosec_save = nosec;
2494         fnosec = fsec = 1;
2495         in_save = in_end = orig;
2496
2497         do {
2498                 if (*in_end == '"')
2499                         open_quote = !open_quote;
2500                 if ((*in_end == ',' && open_quote == 0) ||
2501                                 *in_end == '\0') {
2502                         int len = in_end - in_curr;
2503
2504                         if (selinux_option(in_curr, len))
2505                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2506                         else
2507                                 take_option(&nosec, in_curr, &fnosec, len);
2508
2509                         in_curr = in_end + 1;
2510                 }
2511         } while (*in_end++);
2512
2513         strcpy(in_save, nosec_save);
2514         free_page((unsigned long)nosec_save);
2515 out:
2516         return rc;
2517 }
2518
2519 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2520 {
2521         const struct cred *cred = current_cred();
2522         struct avc_audit_data ad;
2523         int rc;
2524
2525         rc = superblock_doinit(sb, data);
2526         if (rc)
2527                 return rc;
2528
2529         /* Allow all mounts performed by the kernel */
2530         if (flags & MS_KERNMOUNT)
2531                 return 0;
2532
2533         AVC_AUDIT_DATA_INIT(&ad, FS);
2534         ad.u.fs.path.dentry = sb->s_root;
2535         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2536 }
2537
2538 static int selinux_sb_statfs(struct dentry *dentry)
2539 {
2540         const struct cred *cred = current_cred();
2541         struct avc_audit_data ad;
2542
2543         AVC_AUDIT_DATA_INIT(&ad, FS);
2544         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2545         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2546 }
2547
2548 static int selinux_mount(char *dev_name,
2549                          struct path *path,
2550                          char *type,
2551                          unsigned long flags,
2552                          void *data)
2553 {
2554         const struct cred *cred = current_cred();
2555
2556         if (flags & MS_REMOUNT)
2557                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2558                                            FILESYSTEM__REMOUNT, NULL);
2559         else
2560                 return dentry_has_perm(cred, path->mnt, path->dentry,
2561                                        FILE__MOUNTON);
2562 }
2563
2564 static int selinux_umount(struct vfsmount *mnt, int flags)
2565 {
2566         const struct cred *cred = current_cred();
2567
2568         return superblock_has_perm(cred, mnt->mnt_sb,
2569                                    FILESYSTEM__UNMOUNT, NULL);
2570 }
2571
2572 /* inode security operations */
2573
2574 static int selinux_inode_alloc_security(struct inode *inode)
2575 {
2576         return inode_alloc_security(inode);
2577 }
2578
2579 static void selinux_inode_free_security(struct inode *inode)
2580 {
2581         inode_free_security(inode);
2582 }
2583
2584 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2585                                        char **name, void **value,
2586                                        size_t *len)
2587 {
2588         const struct cred *cred = current_cred();
2589         const struct task_security_struct *tsec = cred->security;
2590         struct inode_security_struct *dsec;
2591         struct superblock_security_struct *sbsec;
2592         u32 sid, newsid, clen;
2593         int rc;
2594         char *namep = NULL, *context;
2595
2596         dsec = dir->i_security;
2597         sbsec = dir->i_sb->s_security;
2598
2599         sid = tsec->sid;
2600         newsid = tsec->create_sid;
2601
2602         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2603                 rc = security_transition_sid(sid, dsec->sid,
2604                                              inode_mode_to_security_class(inode->i_mode),
2605                                              &newsid);
2606                 if (rc) {
2607                         printk(KERN_WARNING "%s:  "
2608                                "security_transition_sid failed, rc=%d (dev=%s "
2609                                "ino=%ld)\n",
2610                                __func__,
2611                                -rc, inode->i_sb->s_id, inode->i_ino);
2612                         return rc;
2613                 }
2614         }
2615
2616         /* Possibly defer initialization to selinux_complete_init. */
2617         if (sbsec->flags & SE_SBINITIALIZED) {
2618                 struct inode_security_struct *isec = inode->i_security;
2619                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2620                 isec->sid = newsid;
2621                 isec->initialized = 1;
2622         }
2623
2624         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2625                 return -EOPNOTSUPP;
2626
2627         if (name) {
2628                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2629                 if (!namep)
2630                         return -ENOMEM;
2631                 *name = namep;
2632         }
2633
2634         if (value && len) {
2635                 rc = security_sid_to_context_force(newsid, &context, &clen);
2636                 if (rc) {
2637                         kfree(namep);
2638                         return rc;
2639                 }
2640                 *value = context;
2641                 *len = clen;
2642         }
2643
2644         return 0;
2645 }
2646
2647 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2648 {
2649         return may_create(dir, dentry, SECCLASS_FILE);
2650 }
2651
2652 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2653 {
2654         return may_link(dir, old_dentry, MAY_LINK);
2655 }
2656
2657 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2658 {
2659         return may_link(dir, dentry, MAY_UNLINK);
2660 }
2661
2662 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2663 {
2664         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2665 }
2666
2667 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2668 {
2669         return may_create(dir, dentry, SECCLASS_DIR);
2670 }
2671
2672 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2673 {
2674         return may_link(dir, dentry, MAY_RMDIR);
2675 }
2676
2677 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2678 {
2679         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2680 }
2681
2682 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2683                                 struct inode *new_inode, struct dentry *new_dentry)
2684 {
2685         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2686 }
2687
2688 static int selinux_inode_readlink(struct dentry *dentry)
2689 {
2690         const struct cred *cred = current_cred();
2691
2692         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2693 }
2694
2695 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2696 {
2697         const struct cred *cred = current_cred();
2698
2699         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2700 }
2701
2702 static int selinux_inode_permission(struct inode *inode, int mask)
2703 {
2704         const struct cred *cred = current_cred();
2705
2706         if (!mask) {
2707                 /* No permission to check.  Existence test. */
2708                 return 0;
2709         }
2710
2711         return inode_has_perm(cred, inode,
2712                               file_mask_to_av(inode->i_mode, mask), NULL);
2713 }
2714
2715 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2716 {
2717         const struct cred *cred = current_cred();
2718
2719         if (iattr->ia_valid & ATTR_FORCE)
2720                 return 0;
2721
2722         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2723                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2724                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2725
2726         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2727 }
2728
2729 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2730 {
2731         const struct cred *cred = current_cred();
2732
2733         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2734 }
2735
2736 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2737 {
2738         const struct cred *cred = current_cred();
2739
2740         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2741                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2742                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2743                         if (!capable(CAP_SETFCAP))
2744                                 return -EPERM;
2745                 } else if (!capable(CAP_SYS_ADMIN)) {
2746                         /* A different attribute in the security namespace.
2747                            Restrict to administrator. */
2748                         return -EPERM;
2749                 }
2750         }
2751
2752         /* Not an attribute we recognize, so just check the
2753            ordinary setattr permission. */
2754         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2755 }
2756
2757 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2758                                   const void *value, size_t size, int flags)
2759 {
2760         struct inode *inode = dentry->d_inode;
2761         struct inode_security_struct *isec = inode->i_security;
2762         struct superblock_security_struct *sbsec;
2763         struct avc_audit_data ad;
2764         u32 newsid, sid = current_sid();
2765         int rc = 0;
2766
2767         if (strcmp(name, XATTR_NAME_SELINUX))
2768                 return selinux_inode_setotherxattr(dentry, name);
2769
2770         sbsec = inode->i_sb->s_security;
2771         if (!(sbsec->flags & SE_SBLABELSUPP))
2772                 return -EOPNOTSUPP;
2773
2774         if (!is_owner_or_cap(inode))
2775                 return -EPERM;
2776
2777         AVC_AUDIT_DATA_INIT(&ad, FS);
2778         ad.u.fs.path.dentry = dentry;
2779
2780         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2781                           FILE__RELABELFROM, &ad);
2782         if (rc)
2783                 return rc;
2784
2785         rc = security_context_to_sid(value, size, &newsid);
2786         if (rc == -EINVAL) {
2787                 if (!capable(CAP_MAC_ADMIN))
2788                         return rc;
2789                 rc = security_context_to_sid_force(value, size, &newsid);
2790         }
2791         if (rc)
2792                 return rc;
2793
2794         rc = avc_has_perm(sid, newsid, isec->sclass,
2795                           FILE__RELABELTO, &ad);
2796         if (rc)
2797                 return rc;
2798
2799         rc = security_validate_transition(isec->sid, newsid, sid,
2800                                           isec->sclass);
2801         if (rc)
2802                 return rc;
2803
2804         return avc_has_perm(newsid,
2805                             sbsec->sid,
2806                             SECCLASS_FILESYSTEM,
2807                             FILESYSTEM__ASSOCIATE,
2808                             &ad);
2809 }
2810
2811 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2812                                         const void *value, size_t size,
2813                                         int flags)
2814 {
2815         struct inode *inode = dentry->d_inode;
2816         struct inode_security_struct *isec = inode->i_security;
2817         u32 newsid;
2818         int rc;
2819
2820         if (strcmp(name, XATTR_NAME_SELINUX)) {
2821                 /* Not an attribute we recognize, so nothing to do. */
2822                 return;
2823         }
2824
2825         rc = security_context_to_sid_force(value, size, &newsid);
2826         if (rc) {
2827                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2828                        "for (%s, %lu), rc=%d\n",
2829                        inode->i_sb->s_id, inode->i_ino, -rc);
2830                 return;
2831         }
2832
2833         isec->sid = newsid;
2834         return;
2835 }
2836
2837 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2838 {
2839         const struct cred *cred = current_cred();
2840
2841         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2842 }
2843
2844 static int selinux_inode_listxattr(struct dentry *dentry)
2845 {
2846         const struct cred *cred = current_cred();
2847
2848         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2849 }
2850
2851 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2852 {
2853         if (strcmp(name, XATTR_NAME_SELINUX))
2854                 return selinux_inode_setotherxattr(dentry, name);
2855
2856         /* No one is allowed to remove a SELinux security label.
2857            You can change the label, but all data must be labeled. */
2858         return -EACCES;
2859 }
2860
2861 /*
2862  * Copy the inode security context value to the user.
2863  *
2864  * Permission check is handled by selinux_inode_getxattr hook.
2865  */
2866 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2867 {
2868         u32 size;
2869         int error;
2870         char *context = NULL;
2871         struct inode_security_struct *isec = inode->i_security;
2872
2873         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2874                 return -EOPNOTSUPP;
2875
2876         /*
2877          * If the caller has CAP_MAC_ADMIN, then get the raw context
2878          * value even if it is not defined by current policy; otherwise,
2879          * use the in-core value under current policy.
2880          * Use the non-auditing forms of the permission checks since
2881          * getxattr may be called by unprivileged processes commonly
2882          * and lack of permission just means that we fall back to the
2883          * in-core context value, not a denial.
2884          */
2885         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2886                                 SECURITY_CAP_NOAUDIT);
2887         if (!error)
2888                 error = security_sid_to_context_force(isec->sid, &context,
2889                                                       &size);
2890         else
2891                 error = security_sid_to_context(isec->sid, &context, &size);
2892         if (error)
2893                 return error;
2894         error = size;
2895         if (alloc) {
2896                 *buffer = context;
2897                 goto out_nofree;
2898         }
2899         kfree(context);
2900 out_nofree:
2901         return error;
2902 }
2903
2904 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2905                                      const void *value, size_t size, int flags)
2906 {
2907         struct inode_security_struct *isec = inode->i_security;
2908         u32 newsid;
2909         int rc;
2910
2911         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2912                 return -EOPNOTSUPP;
2913
2914         if (!value || !size)
2915                 return -EACCES;
2916
2917         rc = security_context_to_sid((void *)value, size, &newsid);
2918         if (rc)
2919                 return rc;
2920
2921         isec->sid = newsid;
2922         return 0;
2923 }
2924
2925 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2926 {
2927         const int len = sizeof(XATTR_NAME_SELINUX);
2928         if (buffer && len <= buffer_size)
2929                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2930         return len;
2931 }
2932
2933 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2934 {
2935         struct inode_security_struct *isec = inode->i_security;
2936         *secid = isec->sid;
2937 }
2938
2939 /* file security operations */
2940
2941 static int selinux_revalidate_file_permission(struct file *file, int mask)
2942 {
2943         const struct cred *cred = current_cred();
2944         struct inode *inode = file->f_path.dentry->d_inode;
2945
2946         if (!mask) {
2947                 /* No permission to check.  Existence test. */
2948                 return 0;
2949         }
2950
2951         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2952         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2953                 mask |= MAY_APPEND;
2954
2955         return file_has_perm(cred, file,
2956                              file_mask_to_av(inode->i_mode, mask));
2957 }
2958
2959 static int selinux_file_permission(struct file *file, int mask)
2960 {
2961         if (!mask)
2962                 /* No permission to check.  Existence test. */
2963                 return 0;
2964
2965         return selinux_revalidate_file_permission(file, mask);
2966 }
2967
2968 static int selinux_file_alloc_security(struct file *file)
2969 {
2970         return file_alloc_security(file);
2971 }
2972
2973 static void selinux_file_free_security(struct file *file)
2974 {
2975         file_free_security(file);
2976 }
2977
2978 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2979                               unsigned long arg)
2980 {
2981         const struct cred *cred = current_cred();
2982         u32 av = 0;
2983
2984         if (_IOC_DIR(cmd) & _IOC_WRITE)
2985                 av |= FILE__WRITE;
2986         if (_IOC_DIR(cmd) & _IOC_READ)
2987                 av |= FILE__READ;
2988         if (!av)
2989                 av = FILE__IOCTL;
2990
2991         return file_has_perm(cred, file, av);
2992 }
2993
2994 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2995 {
2996         const struct cred *cred = current_cred();
2997         int rc = 0;
2998
2999 #ifndef CONFIG_PPC32
3000         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3001                 /*
3002                  * We are making executable an anonymous mapping or a
3003                  * private file mapping that will also be writable.
3004                  * This has an additional check.
3005                  */
3006                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3007                 if (rc)
3008                         goto error;
3009         }
3010 #endif
3011
3012         if (file) {
3013                 /* read access is always possible with a mapping */
3014                 u32 av = FILE__READ;
3015
3016                 /* write access only matters if the mapping is shared */
3017                 if (shared && (prot & PROT_WRITE))
3018                         av |= FILE__WRITE;
3019
3020                 if (prot & PROT_EXEC)
3021                         av |= FILE__EXECUTE;
3022
3023                 return file_has_perm(cred, file, av);
3024         }
3025
3026 error:
3027         return rc;
3028 }
3029
3030 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3031                              unsigned long prot, unsigned long flags,
3032                              unsigned long addr, unsigned long addr_only)
3033 {
3034         int rc = 0;
3035         u32 sid = current_sid();
3036
3037         if (addr < mmap_min_addr)
3038                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3039                                   MEMPROTECT__MMAP_ZERO, NULL);
3040         if (rc || addr_only)
3041                 return rc;
3042
3043         if (selinux_checkreqprot)
3044                 prot = reqprot;
3045
3046         return file_map_prot_check(file, prot,
3047                                    (flags & MAP_TYPE) == MAP_SHARED);
3048 }
3049
3050 static int selinux_file_mprotect(struct vm_area_struct *vma,
3051                                  unsigned long reqprot,
3052                                  unsigned long prot)
3053 {
3054         const struct cred *cred = current_cred();
3055
3056         if (selinux_checkreqprot)
3057                 prot = reqprot;
3058
3059 #ifndef CONFIG_PPC32
3060         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3061                 int rc = 0;
3062                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3063                     vma->vm_end <= vma->vm_mm->brk) {
3064                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3065                 } else if (!vma->vm_file &&
3066                            vma->vm_start <= vma->vm_mm->start_stack &&
3067                            vma->vm_end >= vma->vm_mm->start_stack) {
3068                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3069                 } else if (vma->vm_file && vma->anon_vma) {
3070                         /*
3071                          * We are making executable a file mapping that has
3072                          * had some COW done. Since pages might have been
3073                          * written, check ability to execute the possibly
3074                          * modified content.  This typically should only
3075                          * occur for text relocations.
3076                          */
3077                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3078                 }
3079                 if (rc)
3080                         return rc;
3081         }
3082 #endif
3083
3084         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3085 }
3086
3087 static int selinux_file_lock(struct file *file, unsigned int cmd)
3088 {
3089         const struct cred *cred = current_cred();
3090
3091         return file_has_perm(cred, file, FILE__LOCK);
3092 }
3093
3094 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3095                               unsigned long arg)
3096 {
3097         const struct cred *cred = current_cred();
3098         int err = 0;
3099
3100         switch (cmd) {
3101         case F_SETFL:
3102                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3103                         err = -EINVAL;
3104                         break;
3105                 }
3106
3107                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3108                         err = file_has_perm(cred, file, FILE__WRITE);
3109                         break;
3110                 }
3111                 /* fall through */
3112         case F_SETOWN:
3113         case F_SETSIG:
3114         case F_GETFL:
3115         case F_GETOWN:
3116         case F_GETSIG:
3117                 /* Just check FD__USE permission */
3118                 err = file_has_perm(cred, file, 0);
3119                 break;
3120         case F_GETLK:
3121         case F_SETLK:
3122         case F_SETLKW:
3123 #if BITS_PER_LONG == 32
3124         case F_GETLK64:
3125         case F_SETLK64:
3126         case F_SETLKW64:
3127 #endif
3128                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3129                         err = -EINVAL;
3130                         break;
3131                 }
3132                 err = file_has_perm(cred, file, FILE__LOCK);
3133                 break;
3134         }
3135
3136         return err;
3137 }
3138
3139 static int selinux_file_set_fowner(struct file *file)
3140 {
3141         struct file_security_struct *fsec;
3142
3143         fsec = file->f_security;
3144         fsec->fown_sid = current_sid();
3145
3146         return 0;
3147 }
3148
3149 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3150                                        struct fown_struct *fown, int signum)
3151 {
3152         struct file *file;
3153         u32 sid = current_sid();
3154         u32 perm;
3155         struct file_security_struct *fsec;
3156
3157         /* struct fown_struct is never outside the context of a struct file */
3158         file = container_of(fown, struct file, f_owner);
3159
3160         fsec = file->f_security;
3161
3162         if (!signum)
3163                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3164         else
3165                 perm = signal_to_av(signum);
3166
3167         return avc_has_perm(fsec->fown_sid, sid,
3168                             SECCLASS_PROCESS, perm, NULL);
3169 }
3170
3171 static int selinux_file_receive(struct file *file)
3172 {
3173         const struct cred *cred = current_cred();
3174
3175         return file_has_perm(cred, file, file_to_av(file));
3176 }
3177
3178 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3179 {
3180         struct file_security_struct *fsec;
3181         struct inode *inode;
3182         struct inode_security_struct *isec;
3183
3184         inode = file->f_path.dentry->d_inode;
3185         fsec = file->f_security;
3186         isec = inode->i_security;
3187         /*
3188          * Save inode label and policy sequence number
3189          * at open-time so that selinux_file_permission
3190          * can determine whether revalidation is necessary.
3191          * Task label is already saved in the file security
3192          * struct as its SID.
3193          */
3194         fsec->isid = isec->sid;
3195         fsec->pseqno = avc_policy_seqno();
3196         /*
3197          * Since the inode label or policy seqno may have changed
3198          * between the selinux_inode_permission check and the saving
3199          * of state above, recheck that access is still permitted.
3200          * Otherwise, access might never be revalidated against the
3201          * new inode label or new policy.
3202          * This check is not redundant - do not remove.
3203          */
3204         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3205 }
3206
3207 /* task security operations */
3208
3209 static int selinux_task_create(unsigned long clone_flags)
3210 {
3211         return current_has_perm(current, PROCESS__FORK);
3212 }
3213
3214 /*
3215  * detach and free the LSM part of a set of credentials
3216  */
3217 static void selinux_cred_free(struct cred *cred)
3218 {
3219         struct task_security_struct *tsec = cred->security;
3220         cred->security = NULL;
3221         kfree(tsec);
3222 }
3223
3224 /*
3225  * prepare a new set of credentials for modification
3226  */
3227 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3228                                 gfp_t gfp)
3229 {
3230         const struct task_security_struct *old_tsec;
3231         struct task_security_struct *tsec;
3232
3233         old_tsec = old->security;
3234
3235         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3236         if (!tsec)
3237                 return -ENOMEM;
3238
3239         new->security = tsec;
3240         return 0;
3241 }
3242
3243 /*
3244  * set the security data for a kernel service
3245  * - all the creation contexts are set to unlabelled
3246  */
3247 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3248 {
3249         struct task_security_struct *tsec = new->security;
3250         u32 sid = current_sid();
3251         int ret;
3252
3253         ret = avc_has_perm(sid, secid,
3254                            SECCLASS_KERNEL_SERVICE,
3255                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3256                            NULL);
3257         if (ret == 0) {
3258                 tsec->sid = secid;
3259                 tsec->create_sid = 0;
3260                 tsec->keycreate_sid = 0;
3261                 tsec->sockcreate_sid = 0;
3262         }
3263         return ret;
3264 }
3265
3266 /*
3267  * set the file creation context in a security record to the same as the
3268  * objective context of the specified inode
3269  */
3270 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3271 {
3272         struct inode_security_struct *isec = inode->i_security;
3273         struct task_security_struct *tsec = new->security;
3274         u32 sid = current_sid();
3275         int ret;
3276
3277         ret = avc_has_perm(sid, isec->sid,
3278                            SECCLASS_KERNEL_SERVICE,
3279                            KERNEL_SERVICE__CREATE_FILES_AS,
3280                            NULL);
3281
3282         if (ret == 0)
3283                 tsec->create_sid = isec->sid;
3284         return 0;
3285 }
3286
3287 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3288 {
3289         return current_has_perm(p, PROCESS__SETPGID);
3290 }
3291
3292 static int selinux_task_getpgid(struct task_struct *p)
3293 {
3294         return current_has_perm(p, PROCESS__GETPGID);
3295 }
3296
3297 static int selinux_task_getsid(struct task_struct *p)
3298 {
3299         return current_has_perm(p, PROCESS__GETSESSION);
3300 }
3301
3302 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3303 {
3304         *secid = task_sid(p);
3305 }
3306
3307 static int selinux_task_setnice(struct task_struct *p, int nice)
3308 {
3309         int rc;
3310
3311         rc = cap_task_setnice(p, nice);
3312         if (rc)
3313                 return rc;
3314
3315         return current_has_perm(p, PROCESS__SETSCHED);
3316 }
3317
3318 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3319 {
3320         int rc;
3321
3322         rc = cap_task_setioprio(p, ioprio);
3323         if (rc)
3324                 return rc;
3325
3326         return current_has_perm(p, PROCESS__SETSCHED);
3327 }
3328
3329 static int selinux_task_getioprio(struct task_struct *p)
3330 {
3331         return current_has_perm(p, PROCESS__GETSCHED);
3332 }
3333
3334 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3335 {
3336         struct rlimit *old_rlim = current->signal->rlim + resource;
3337
3338         /* Control the ability to change the hard limit (whether
3339            lowering or raising it), so that the hard limit can
3340            later be used as a safe reset point for the soft limit
3341            upon context transitions.  See selinux_bprm_committing_creds. */
3342         if (old_rlim->rlim_max != new_rlim->rlim_max)
3343                 return current_has_perm(current, PROCESS__SETRLIMIT);
3344
3345         return 0;
3346 }
3347
3348 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3349 {
3350         int rc;
3351
3352         rc = cap_task_setscheduler(p, policy, lp);
3353         if (rc)
3354                 return rc;
3355
3356         return current_has_perm(p, PROCESS__SETSCHED);
3357 }
3358
3359 static int selinux_task_getscheduler(struct task_struct *p)
3360 {
3361         return current_has_perm(p, PROCESS__GETSCHED);
3362 }
3363
3364 static int selinux_task_movememory(struct task_struct *p)
3365 {
3366         return current_has_perm(p, PROCESS__SETSCHED);
3367 }
3368
3369 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3370                                 int sig, u32 secid)
3371 {
3372         u32 perm;
3373         int rc;
3374
3375         if (!sig)
3376                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3377         else
3378                 perm = signal_to_av(sig);
3379         if (secid)
3380                 rc = avc_has_perm(secid, task_sid(p),
3381                                   SECCLASS_PROCESS, perm, NULL);
3382         else
3383                 rc = current_has_perm(p, perm);
3384         return rc;
3385 }
3386
3387 static int selinux_task_wait(struct task_struct *p)
3388 {
3389         return task_has_perm(p, current, PROCESS__SIGCHLD);
3390 }
3391
3392 static void selinux_task_to_inode(struct task_struct *p,
3393                                   struct inode *inode)
3394 {
3395         struct inode_security_struct *isec = inode->i_security;
3396         u32 sid = task_sid(p);
3397
3398         isec->sid = sid;
3399         isec->initialized = 1;
3400 }
3401
3402 /* Returns error only if unable to parse addresses */
3403 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3404                         struct avc_audit_data *ad, u8 *proto)
3405 {
3406         int offset, ihlen, ret = -EINVAL;
3407         struct iphdr _iph, *ih;
3408
3409         offset = skb_network_offset(skb);
3410         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3411         if (ih == NULL)
3412                 goto out;
3413
3414         ihlen = ih->ihl * 4;
3415         if (ihlen < sizeof(_iph))
3416                 goto out;
3417
3418         ad->u.net.v4info.saddr = ih->saddr;
3419         ad->u.net.v4info.daddr = ih->daddr;
3420         ret = 0;
3421
3422         if (proto)
3423                 *proto = ih->protocol;
3424
3425         switch (ih->protocol) {
3426         case IPPROTO_TCP: {
3427                 struct tcphdr _tcph, *th;
3428
3429                 if (ntohs(ih->frag_off) & IP_OFFSET)
3430                         break;
3431
3432                 offset += ihlen;
3433                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3434                 if (th == NULL)
3435                         break;
3436
3437                 ad->u.net.sport = th->source;
3438                 ad->u.net.dport = th->dest;
3439                 break;
3440         }
3441
3442         case IPPROTO_UDP: {
3443                 struct udphdr _udph, *uh;
3444
3445                 if (ntohs(ih->frag_off) & IP_OFFSET)
3446                         break;
3447
3448                 offset += ihlen;
3449                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3450                 if (uh == NULL)
3451                         break;
3452
3453                 ad->u.net.sport = uh->source;
3454                 ad->u.net.dport = uh->dest;
3455                 break;
3456         }
3457
3458         case IPPROTO_DCCP: {
3459                 struct dccp_hdr _dccph, *dh;
3460
3461                 if (ntohs(ih->frag_off) & IP_OFFSET)
3462                         break;
3463
3464                 offset += ihlen;
3465                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3466                 if (dh == NULL)
3467                         break;
3468
3469                 ad->u.net.sport = dh->dccph_sport;
3470                 ad->u.net.dport = dh->dccph_dport;
3471                 break;
3472         }
3473
3474         default:
3475                 break;
3476         }
3477 out:
3478         return ret;
3479 }
3480
3481 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3482
3483 /* Returns error only if unable to parse addresses */
3484 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3485                         struct avc_audit_data *ad, u8 *proto)
3486 {
3487         u8 nexthdr;
3488         int ret = -EINVAL, offset;
3489         struct ipv6hdr _ipv6h, *ip6;
3490
3491         offset = skb_network_offset(skb);
3492         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3493         if (ip6 == NULL)
3494                 goto out;
3495
3496         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3497         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3498         ret = 0;
3499
3500         nexthdr = ip6->nexthdr;
3501         offset += sizeof(_ipv6h);
3502         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3503         if (offset < 0)
3504                 goto out;
3505
3506         if (proto)
3507                 *proto = nexthdr;
3508
3509         switch (nexthdr) {
3510         case IPPROTO_TCP: {
3511                 struct tcphdr _tcph, *th;
3512
3513                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3514                 if (th == NULL)
3515                         break;
3516
3517                 ad->u.net.sport = th->source;
3518                 ad->u.net.dport = th->dest;
3519                 break;
3520         }
3521
3522         case IPPROTO_UDP: {
3523                 struct udphdr _udph, *uh;
3524
3525                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3526                 if (uh == NULL)
3527                         break;
3528
3529                 ad->u.net.sport = uh->source;
3530                 ad->u.net.dport = uh->dest;
3531                 break;
3532         }
3533
3534         case IPPROTO_DCCP: {
3535                 struct dccp_hdr _dccph, *dh;
3536
3537                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3538                 if (dh == NULL)
3539                         break;
3540
3541                 ad->u.net.sport = dh->dccph_sport;
3542                 ad->u.net.dport = dh->dccph_dport;
3543                 break;
3544         }
3545
3546         /* includes fragments */
3547         default:
3548                 break;
3549         }
3550 out:
3551         return ret;
3552 }
3553
3554 #endif /* IPV6 */
3555
3556 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3557                              char **_addrp, int src, u8 *proto)
3558 {
3559         char *addrp;
3560         int ret;
3561
3562         switch (ad->u.net.family) {
3563         case PF_INET:
3564                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3565                 if (ret)
3566                         goto parse_error;
3567                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3568                                        &ad->u.net.v4info.daddr);
3569                 goto okay;
3570
3571 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3572         case PF_INET6:
3573                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3574                 if (ret)
3575                         goto parse_error;
3576                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3577                                        &ad->u.net.v6info.daddr);
3578                 goto okay;
3579 #endif  /* IPV6 */
3580         default:
3581                 addrp = NULL;
3582                 goto okay;
3583         }
3584
3585 parse_error:
3586         printk(KERN_WARNING
3587                "SELinux: failure in selinux_parse_skb(),"
3588                " unable to parse packet\n");
3589         return ret;
3590
3591 okay:
3592         if (_addrp)
3593                 *_addrp = addrp;
3594         return 0;
3595 }
3596
3597 /**
3598  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3599  * @skb: the packet
3600  * @family: protocol family
3601  * @sid: the packet's peer label SID
3602  *
3603  * Description:
3604  * Check the various different forms of network peer labeling and determine
3605  * the peer label/SID for the packet; most of the magic actually occurs in
3606  * the security server function security_net_peersid_cmp().  The function
3607  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3608  * or -EACCES if @sid is invalid due to inconsistencies with the different
3609  * peer labels.
3610  *
3611  */
3612 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3613 {
3614         int err;
3615         u32 xfrm_sid;
3616         u32 nlbl_sid;
3617         u32 nlbl_type;
3618
3619         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3620         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3621
3622         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3623         if (unlikely(err)) {
3624                 printk(KERN_WARNING
3625                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3626                        " unable to determine packet's peer label\n");
3627                 return -EACCES;
3628         }
3629
3630         return 0;
3631 }
3632
3633 /* socket security operations */
3634 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3635                            u32 perms)
3636 {
3637         struct inode_security_struct *isec;
3638         struct avc_audit_data ad;
3639         u32 sid;
3640         int err = 0;
3641
3642         isec = SOCK_INODE(sock)->i_security;
3643
3644         if (isec->sid == SECINITSID_KERNEL)
3645                 goto out;
3646         sid = task_sid(task);
3647
3648         AVC_AUDIT_DATA_INIT(&ad, NET);
3649         ad.u.net.sk = sock->sk;
3650         err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
3651
3652 out:
3653         return err;
3654 }
3655
3656 static int selinux_socket_create(int family, int type,
3657                                  int protocol, int kern)
3658 {
3659         const struct cred *cred = current_cred();
3660         const struct task_security_struct *tsec = cred->security;
3661         u32 sid, newsid;
3662         u16 secclass;
3663         int err = 0;
3664
3665         if (kern)
3666                 goto out;
3667
3668         sid = tsec->sid;
3669         newsid = tsec->sockcreate_sid ?: sid;
3670
3671         secclass = socket_type_to_security_class(family, type, protocol);
3672         err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
3673
3674 out:
3675         return err;
3676 }
3677
3678 static int selinux_socket_post_create(struct socket *sock, int family,
3679                                       int type, int protocol, int kern)
3680 {
3681         const struct cred *cred = current_cred();
3682         const struct task_security_struct *tsec = cred->security;
3683         struct inode_security_struct *isec;
3684         struct sk_security_struct *sksec;
3685         u32 sid, newsid;
3686         int err = 0;
3687
3688         sid = tsec->sid;
3689         newsid = tsec->sockcreate_sid;
3690
3691         isec = SOCK_INODE(sock)->i_security;
3692
3693         if (kern)
3694                 isec->sid = SECINITSID_KERNEL;
3695         else if (newsid)
3696                 isec->sid = newsid;
3697         else
3698                 isec->sid = sid;
3699
3700         isec->sclass = socket_type_to_security_class(family, type, protocol);
3701         isec->initialized = 1;
3702
3703         if (sock->sk) {
3704                 sksec = sock->sk->sk_security;
3705                 sksec->sid = isec->sid;
3706                 sksec->sclass = isec->sclass;
3707                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3708         }
3709
3710         return err;
3711 }
3712
3713 /* Range of port numbers used to automatically bind.
3714    Need to determine whether we should perform a name_bind
3715    permission check between the socket and the port number. */
3716
3717 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3718 {
3719         u16 family;
3720         int err;
3721
3722         err = socket_has_perm(current, sock, SOCKET__BIND);
3723         if (err)
3724                 goto out;
3725
3726         /*
3727          * If PF_INET or PF_INET6, check name_bind permission for the port.
3728          * Multiple address binding for SCTP is not supported yet: we just
3729          * check the first address now.
3730          */
3731         family = sock->sk->sk_family;
3732         if (family == PF_INET || family == PF_INET6) {
3733                 char *addrp;
3734                 struct inode_security_struct *isec;
3735                 struct avc_audit_data ad;
3736                 struct sockaddr_in *addr4 = NULL;
3737                 struct sockaddr_in6 *addr6 = NULL;
3738                 unsigned short snum;
3739                 struct sock *sk = sock->sk;
3740                 u32 sid, node_perm;
3741
3742                 isec = SOCK_INODE(sock)->i_security;
3743
3744                 if (family == PF_INET) {
3745                         addr4 = (struct sockaddr_in *)address;
3746                         snum = ntohs(addr4->sin_port);
3747                         addrp = (char *)&addr4->sin_addr.s_addr;
3748                 } else {
3749                         addr6 = (struct sockaddr_in6 *)address;
3750                         snum = ntohs(addr6->sin6_port);
3751                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3752                 }
3753
3754                 if (snum) {
3755                         int low, high;
3756
3757                         inet_get_local_port_range(&low, &high);
3758
3759                         if (snum < max(PROT_SOCK, low) || snum > high) {
3760                                 err = sel_netport_sid(sk->sk_protocol,
3761                                                       snum, &sid);
3762                                 if (err)
3763                                         goto out;
3764                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3765                                 ad.u.net.sport = htons(snum);
3766                                 ad.u.net.family = family;
3767                                 err = avc_has_perm(isec->sid, sid,
3768                                                    isec->sclass,
3769                                                    SOCKET__NAME_BIND, &ad);
3770                                 if (err)
3771                                         goto out;
3772                         }
3773                 }
3774
3775                 switch (isec->sclass) {
3776                 case SECCLASS_TCP_SOCKET:
3777                         node_perm = TCP_SOCKET__NODE_BIND;
3778                         break;
3779
3780                 case SECCLASS_UDP_SOCKET:
3781                         node_perm = UDP_SOCKET__NODE_BIND;
3782                         break;
3783
3784                 case SECCLASS_DCCP_SOCKET:
3785                         node_perm = DCCP_SOCKET__NODE_BIND;
3786                         break;
3787
3788                 default:
3789                         node_perm = RAWIP_SOCKET__NODE_BIND;
3790                         break;
3791                 }
3792
3793                 err = sel_netnode_sid(addrp, family, &sid);
3794                 if (err)
3795                         goto out;
3796
3797                 AVC_AUDIT_DATA_INIT(&ad, NET);
3798                 ad.u.net.sport = htons(snum);
3799                 ad.u.net.family = family;
3800
3801                 if (family == PF_INET)
3802                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3803                 else
3804                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3805
3806                 err = avc_has_perm(isec->sid, sid,
3807                                    isec->sclass, node_perm, &ad);
3808                 if (err)
3809                         goto out;
3810         }
3811 out:
3812         return err;
3813 }
3814
3815 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3816 {
3817         struct sock *sk = sock->sk;
3818         struct inode_security_struct *isec;
3819         int err;
3820
3821         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3822         if (err)
3823                 return err;
3824
3825         /*
3826          * If a TCP or DCCP socket, check name_connect permission for the port.
3827          */
3828         isec = SOCK_INODE(sock)->i_security;
3829         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3830             isec->sclass == SECCLASS_DCCP_SOCKET) {
3831                 struct avc_audit_data ad;
3832                 struct sockaddr_in *addr4 = NULL;
3833                 struct sockaddr_in6 *addr6 = NULL;
3834                 unsigned short snum;
3835                 u32 sid, perm;
3836
3837                 if (sk->sk_family == PF_INET) {
3838                         addr4 = (struct sockaddr_in *)address;
3839                         if (addrlen < sizeof(struct sockaddr_in))
3840                                 return -EINVAL;
3841                         snum = ntohs(addr4->sin_port);
3842                 } else {
3843                         addr6 = (struct sockaddr_in6 *)address;
3844                         if (addrlen < SIN6_LEN_RFC2133)
3845                                 return -EINVAL;
3846                         snum = ntohs(addr6->sin6_port);
3847                 }
3848
3849                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3850                 if (err)
3851                         goto out;
3852
3853                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3854                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3855
3856                 AVC_AUDIT_DATA_INIT(&ad, NET);
3857                 ad.u.net.dport = htons(snum);
3858                 ad.u.net.family = sk->sk_family;
3859                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3860                 if (err)
3861                         goto out;
3862         }
3863
3864         err = selinux_netlbl_socket_connect(sk, address);
3865
3866 out:
3867         return err;
3868 }
3869
3870 static int selinux_socket_listen(struct socket *sock, int backlog)
3871 {
3872         return socket_has_perm(current, sock, SOCKET__LISTEN);
3873 }
3874
3875 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3876 {
3877         int err;
3878         struct inode_security_struct *isec;
3879         struct inode_security_struct *newisec;
3880
3881         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3882         if (err)
3883                 return err;
3884
3885         newisec = SOCK_INODE(newsock)->i_security;
3886
3887         isec = SOCK_INODE(sock)->i_security;
3888         newisec->sclass = isec->sclass;
3889         newisec->sid = isec->sid;
3890         newisec->initialized = 1;
3891
3892         return 0;
3893 }
3894
3895 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3896                                   int size)
3897 {
3898         return socket_has_perm(current, sock, SOCKET__WRITE);
3899 }
3900
3901 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3902                                   int size, int flags)
3903 {
3904         return socket_has_perm(current, sock, SOCKET__READ);
3905 }
3906
3907 static int selinux_socket_getsockname(struct socket *sock)
3908 {
3909         return socket_has_perm(current, sock, SOCKET__GETATTR);
3910 }
3911
3912 static int selinux_socket_getpeername(struct socket *sock)
3913 {
3914         return socket_has_perm(current, sock, SOCKET__GETATTR);
3915 }
3916
3917 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3918 {
3919         int err;
3920
3921         err = socket_has_perm(current, sock, SOCKET__SETOPT);
3922         if (err)
3923                 return err;
3924
3925         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3926 }
3927
3928 static int selinux_socket_getsockopt(struct socket *sock, int level,
3929                                      int optname)
3930 {
3931         return socket_has_perm(current, sock, SOCKET__GETOPT);
3932 }
3933
3934 static int selinux_socket_shutdown(struct socket *sock, int how)
3935 {
3936         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3937 }
3938
3939 static int selinux_socket_unix_stream_connect(struct socket *sock,
3940                                               struct socket *other,
3941                                               struct sock *newsk)
3942 {
3943         struct sk_security_struct *ssec;
3944         struct inode_security_struct *isec;
3945         struct inode_security_struct *other_isec;
3946         struct avc_audit_data ad;
3947         int err;
3948
3949         isec = SOCK_INODE(sock)->i_security;
3950         other_isec = SOCK_INODE(other)->i_security;
3951
3952         AVC_AUDIT_DATA_INIT(&ad, NET);
3953         ad.u.net.sk = other->sk;
3954
3955         err = avc_has_perm(isec->sid, other_isec->sid,
3956                            isec->sclass,
3957                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3958         if (err)
3959                 return err;
3960
3961         /* connecting socket */
3962         ssec = sock->sk->sk_security;
3963         ssec->peer_sid = other_isec->sid;
3964
3965         /* server child socket */
3966         ssec = newsk->sk_security;
3967         ssec->peer_sid = isec->sid;
3968         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
3969
3970         return err;
3971 }
3972
3973 static int selinux_socket_unix_may_send(struct socket *sock,
3974                                         struct socket *other)
3975 {
3976         struct inode_security_struct *isec;
3977         struct inode_security_struct *other_isec;
3978         struct avc_audit_data ad;
3979         int err;
3980
3981         isec = SOCK_INODE(sock)->i_security;
3982         other_isec = SOCK_INODE(other)->i_security;
3983
3984         AVC_AUDIT_DATA_INIT(&ad, NET);
3985         ad.u.net.sk = other->sk;
3986
3987         err = avc_has_perm(isec->sid, other_isec->sid,
3988                            isec->sclass, SOCKET__SENDTO, &ad);
3989         if (err)
3990                 return err;
3991
3992         return 0;
3993 }
3994
3995 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3996                                     u32 peer_sid,
3997                                     struct avc_audit_data *ad)
3998 {
3999         int err;
4000         u32 if_sid;
4001         u32 node_sid;
4002
4003         err = sel_netif_sid(ifindex, &if_sid);
4004         if (err)
4005                 return err;
4006         err = avc_has_perm(peer_sid, if_sid,
4007                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4008         if (err)
4009                 return err;
4010
4011         err = sel_netnode_sid(addrp, family, &node_sid);
4012         if (err)
4013                 return err;
4014         return avc_has_perm(peer_sid, node_sid,
4015                             SECCLASS_NODE, NODE__RECVFROM, ad);
4016 }
4017
4018 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4019                                        u16 family)
4020 {
4021         int err = 0;
4022         struct sk_security_struct *sksec = sk->sk_security;
4023         u32 peer_sid;
4024         u32 sk_sid = sksec->sid;
4025         struct avc_audit_data ad;
4026         char *addrp;
4027
4028         AVC_AUDIT_DATA_INIT(&ad, NET);
4029         ad.u.net.netif = skb->iif;
4030         ad.u.net.family = family;
4031         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4032         if (err)
4033                 return err;
4034
4035         if (selinux_secmark_enabled()) {
4036                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4037                                    PACKET__RECV, &ad);
4038                 if (err)
4039                         return err;
4040         }
4041
4042         if (selinux_policycap_netpeer) {
4043                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4044                 if (err)
4045                         return err;
4046                 err = avc_has_perm(sk_sid, peer_sid,
4047                                    SECCLASS_PEER, PEER__RECV, &ad);
4048                 if (err)
4049                         selinux_netlbl_err(skb, err, 0);
4050         } else {
4051                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4052                 if (err)
4053                         return err;
4054                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4055         }
4056
4057         return err;
4058 }
4059
4060 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4061 {
4062         int err;
4063         struct sk_security_struct *sksec = sk->sk_security;
4064         u16 family = sk->sk_family;
4065         u32 sk_sid = sksec->sid;
4066         struct avc_audit_data ad;
4067         char *addrp;
4068         u8 secmark_active;
4069         u8 peerlbl_active;
4070
4071         if (family != PF_INET && family != PF_INET6)
4072                 return 0;
4073
4074         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4075         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4076                 family = PF_INET;
4077
4078         /* If any sort of compatibility mode is enabled then handoff processing
4079          * to the selinux_sock_rcv_skb_compat() function to deal with the
4080          * special handling.  We do this in an attempt to keep this function
4081          * as fast and as clean as possible. */
4082         if (!selinux_policycap_netpeer)
4083                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4084
4085         secmark_active = selinux_secmark_enabled();
4086         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4087         if (!secmark_active && !peerlbl_active)
4088                 return 0;
4089
4090         AVC_AUDIT_DATA_INIT(&ad, NET);
4091         ad.u.net.netif = skb->iif;
4092         ad.u.net.family = family;
4093         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4094         if (err)
4095                 return err;
4096
4097         if (peerlbl_active) {
4098                 u32 peer_sid;
4099
4100                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4101                 if (err)
4102                         return err;
4103                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4104                                                peer_sid, &ad);
4105                 if (err) {
4106                         selinux_netlbl_err(skb, err, 0);
4107                         return err;
4108                 }
4109                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4110                                    PEER__RECV, &ad);
4111                 if (err)
4112                         selinux_netlbl_err(skb, err, 0);
4113         }
4114
4115         if (secmark_active) {
4116                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4117                                    PACKET__RECV, &ad);
4118                 if (err)
4119                         return err;
4120         }
4121
4122         return err;
4123 }
4124
4125 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4126                                             int __user *optlen, unsigned len)
4127 {
4128         int err = 0;
4129         char *scontext;
4130         u32 scontext_len;
4131         struct sk_security_struct *ssec;
4132         struct inode_security_struct *isec;
4133         u32 peer_sid = SECSID_NULL;
4134
4135         isec = SOCK_INODE(sock)->i_security;
4136
4137         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4138             isec->sclass == SECCLASS_TCP_SOCKET) {
4139                 ssec = sock->sk->sk_security;
4140                 peer_sid = ssec->peer_sid;
4141         }
4142         if (peer_sid == SECSID_NULL) {
4143                 err = -ENOPROTOOPT;
4144                 goto out;
4145         }
4146
4147         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4148
4149         if (err)
4150                 goto out;
4151
4152         if (scontext_len > len) {
4153                 err = -ERANGE;
4154                 goto out_len;
4155         }
4156
4157         if (copy_to_user(optval, scontext, scontext_len))
4158                 err = -EFAULT;
4159
4160 out_len:
4161         if (put_user(scontext_len, optlen))
4162                 err = -EFAULT;
4163
4164         kfree(scontext);
4165 out:
4166         return err;
4167 }
4168
4169 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4170 {
4171         u32 peer_secid = SECSID_NULL;
4172         u16 family;
4173
4174         if (skb && skb->protocol == htons(ETH_P_IP))
4175                 family = PF_INET;
4176         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4177                 family = PF_INET6;
4178         else if (sock)
4179                 family = sock->sk->sk_family;
4180         else
4181                 goto out;
4182
4183         if (sock && family == PF_UNIX)
4184                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4185         else if (skb)
4186                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4187
4188 out:
4189         *secid = peer_secid;
4190         if (peer_secid == SECSID_NULL)
4191                 return -EINVAL;
4192         return 0;
4193 }
4194
4195 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4196 {
4197         return sk_alloc_security(sk, family, priority);
4198 }
4199
4200 static void selinux_sk_free_security(struct sock *sk)
4201 {
4202         sk_free_security(sk);
4203 }
4204
4205 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4206 {
4207         struct sk_security_struct *ssec = sk->sk_security;
4208         struct sk_security_struct *newssec = newsk->sk_security;
4209
4210         newssec->sid = ssec->sid;
4211         newssec->peer_sid = ssec->peer_sid;
4212         newssec->sclass = ssec->sclass;
4213
4214         selinux_netlbl_sk_security_reset(newssec);
4215 }
4216
4217 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4218 {
4219         if (!sk)
4220                 *secid = SECINITSID_ANY_SOCKET;
4221         else {
4222                 struct sk_security_struct *sksec = sk->sk_security;
4223
4224                 *secid = sksec->sid;
4225         }
4226 }
4227
4228 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4229 {
4230         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4231         struct sk_security_struct *sksec = sk->sk_security;
4232
4233         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4234             sk->sk_family == PF_UNIX)
4235                 isec->sid = sksec->sid;
4236         sksec->sclass = isec->sclass;
4237 }
4238
4239 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4240                                      struct request_sock *req)
4241 {
4242         struct sk_security_struct *sksec = sk->sk_security;
4243         int err;
4244         u16 family = sk->sk_family;
4245         u32 newsid;
4246         u32 peersid;
4247
4248         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4249         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4250                 family = PF_INET;
4251
4252         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4253         if (err)
4254                 return err;
4255         if (peersid == SECSID_NULL) {
4256                 req->secid = sksec->sid;
4257                 req->peer_secid = SECSID_NULL;
4258         } else {
4259                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4260                 if (err)
4261                         return err;
4262                 req->secid = newsid;
4263                 req->peer_secid = peersid;
4264         }
4265
4266         return selinux_netlbl_inet_conn_request(req, family);
4267 }
4268
4269 static void selinux_inet_csk_clone(struct sock *newsk,
4270                                    const struct request_sock *req)
4271 {
4272         struct sk_security_struct *newsksec = newsk->sk_security;
4273
4274         newsksec->sid = req->secid;
4275         newsksec->peer_sid = req->peer_secid;
4276         /* NOTE: Ideally, we should also get the isec->sid for the
4277            new socket in sync, but we don't have the isec available yet.
4278            So we will wait until sock_graft to do it, by which
4279            time it will have been created and available. */
4280
4281         /* We don't need to take any sort of lock here as we are the only
4282          * thread with access to newsksec */
4283         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4284 }
4285
4286 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4287 {
4288         u16 family = sk->sk_family;
4289         struct sk_security_struct *sksec = sk->sk_security;
4290
4291         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4292         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4293                 family = PF_INET;
4294
4295         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4296 }
4297
4298 static void selinux_req_classify_flow(const struct request_sock *req,
4299                                       struct flowi *fl)
4300 {
4301         fl->secid = req->secid;
4302 }
4303
4304 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4305 {
4306         int err = 0;
4307         u32 perm;
4308         struct nlmsghdr *nlh;
4309         struct socket *sock = sk->sk_socket;
4310         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4311
4312         if (skb->len < NLMSG_SPACE(0)) {
4313                 err = -EINVAL;
4314                 goto out;
4315         }
4316         nlh = nlmsg_hdr(skb);
4317
4318         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4319         if (err) {
4320                 if (err == -EINVAL) {
4321                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4322                                   "SELinux:  unrecognized netlink message"
4323                                   " type=%hu for sclass=%hu\n",
4324                                   nlh->nlmsg_type, isec->sclass);
4325                         if (!selinux_enforcing || security_get_allow_unknown())
4326                                 err = 0;
4327                 }
4328
4329                 /* Ignore */
4330                 if (err == -ENOENT)
4331                         err = 0;
4332                 goto out;
4333         }
4334
4335         err = socket_has_perm(current, sock, perm);
4336 out:
4337         return err;
4338 }
4339
4340 #ifdef CONFIG_NETFILTER
4341
4342 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4343                                        u16 family)
4344 {
4345         int err;
4346         char *addrp;
4347         u32 peer_sid;
4348         struct avc_audit_data ad;
4349         u8 secmark_active;
4350         u8 netlbl_active;
4351         u8 peerlbl_active;
4352
4353         if (!selinux_policycap_netpeer)
4354                 return NF_ACCEPT;
4355
4356         secmark_active = selinux_secmark_enabled();
4357         netlbl_active = netlbl_enabled();
4358         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4359         if (!secmark_active && !peerlbl_active)
4360                 return NF_ACCEPT;
4361
4362         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4363                 return NF_DROP;
4364
4365         AVC_AUDIT_DATA_INIT(&ad, NET);
4366         ad.u.net.netif = ifindex;
4367         ad.u.net.family = family;
4368         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4369                 return NF_DROP;
4370
4371         if (peerlbl_active) {
4372                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4373                                                peer_sid, &ad);
4374                 if (err) {
4375                         selinux_netlbl_err(skb, err, 1);
4376                         return NF_DROP;
4377                 }
4378         }
4379
4380         if (secmark_active)
4381                 if (avc_has_perm(peer_sid, skb->secmark,
4382                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4383                         return NF_DROP;
4384
4385         if (netlbl_active)
4386                 /* we do this in the FORWARD path and not the POST_ROUTING
4387                  * path because we want to make sure we apply the necessary
4388                  * labeling before IPsec is applied so we can leverage AH
4389                  * protection */
4390                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4391                         return NF_DROP;
4392
4393         return NF_ACCEPT;
4394 }
4395
4396 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4397                                          struct sk_buff *skb,
4398                                          const struct net_device *in,
4399                                          const struct net_device *out,
4400                                          int (*okfn)(struct sk_buff *))
4401 {
4402         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4403 }
4404
4405 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4406 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4407                                          struct sk_buff *skb,
4408                                          const struct net_device *in,
4409                                          const struct net_device *out,
4410                                          int (*okfn)(struct sk_buff *))
4411 {
4412         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4413 }
4414 #endif  /* IPV6 */
4415
4416 static unsigned int selinux_ip_output(struct sk_buff *skb,
4417                                       u16 family)
4418 {
4419         u32 sid;
4420
4421         if (!netlbl_enabled())
4422                 return NF_ACCEPT;
4423
4424         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4425          * because we want to make sure we apply the necessary labeling
4426          * before IPsec is applied so we can leverage AH protection */
4427         if (skb->sk) {
4428                 struct sk_security_struct *sksec = skb->sk->sk_security;
4429                 sid = sksec->sid;
4430         } else
4431                 sid = SECINITSID_KERNEL;
4432         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4433                 return NF_DROP;
4434
4435         return NF_ACCEPT;
4436 }
4437
4438 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4439                                         struct sk_buff *skb,
4440                                         const struct net_device *in,
4441                                         const struct net_device *out,
4442                                         int (*okfn)(struct sk_buff *))
4443 {
4444         return selinux_ip_output(skb, PF_INET);
4445 }
4446
4447 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4448                                                 int ifindex,
4449                                                 u16 family)
4450 {
4451         struct sock *sk = skb->sk;
4452         struct sk_security_struct *sksec;
4453         struct avc_audit_data ad;
4454         char *addrp;
4455         u8 proto;
4456
4457         if (sk == NULL)
4458                 return NF_ACCEPT;
4459         sksec = sk->sk_security;
4460
4461         AVC_AUDIT_DATA_INIT(&ad, NET);
4462         ad.u.net.netif = ifindex;
4463         ad.u.net.family = family;
4464         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4465                 return NF_DROP;
4466
4467         if (selinux_secmark_enabled())
4468                 if (avc_has_perm(sksec->sid, skb->secmark,
4469                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4470                         return NF_DROP;
4471
4472         if (selinux_policycap_netpeer)
4473                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4474                         return NF_DROP;
4475
4476         return NF_ACCEPT;
4477 }
4478
4479 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4480                                          u16 family)
4481 {
4482         u32 secmark_perm;
4483         u32 peer_sid;
4484         struct sock *sk;
4485         struct avc_audit_data ad;
4486         char *addrp;
4487         u8 secmark_active;
4488         u8 peerlbl_active;
4489
4490         /* If any sort of compatibility mode is enabled then handoff processing
4491          * to the selinux_ip_postroute_compat() function to deal with the
4492          * special handling.  We do this in an attempt to keep this function
4493          * as fast and as clean as possible. */
4494         if (!selinux_policycap_netpeer)
4495                 return selinux_ip_postroute_compat(skb, ifindex, family);
4496 #ifdef CONFIG_XFRM
4497         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4498          * packet transformation so allow the packet to pass without any checks
4499          * since we'll have another chance to perform access control checks
4500          * when the packet is on it's final way out.
4501          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4502          *       is NULL, in this case go ahead and apply access control. */
4503         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4504                 return NF_ACCEPT;
4505 #endif
4506         secmark_active = selinux_secmark_enabled();
4507         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4508         if (!secmark_active && !peerlbl_active)
4509                 return NF_ACCEPT;
4510
4511         /* if the packet is being forwarded then get the peer label from the
4512          * packet itself; otherwise check to see if it is from a local
4513          * application or the kernel, if from an application get the peer label
4514          * from the sending socket, otherwise use the kernel's sid */
4515         sk = skb->sk;
4516         if (sk == NULL) {
4517                 switch (family) {
4518                 case PF_INET:
4519                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4520                                 secmark_perm = PACKET__FORWARD_OUT;
4521                         else
4522                                 secmark_perm = PACKET__SEND;
4523                         break;
4524                 case PF_INET6:
4525                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4526                                 secmark_perm = PACKET__FORWARD_OUT;
4527                         else
4528                                 secmark_perm = PACKET__SEND;
4529                         break;
4530                 default:
4531                         return NF_DROP;
4532                 }
4533                 if (secmark_perm == PACKET__FORWARD_OUT) {
4534                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4535                                 return NF_DROP;
4536                 } else
4537                         peer_sid = SECINITSID_KERNEL;
4538         } else {
4539                 struct sk_security_struct *sksec = sk->sk_security;
4540                 peer_sid = sksec->sid;
4541                 secmark_perm = PACKET__SEND;
4542         }
4543
4544         AVC_AUDIT_DATA_INIT(&ad, NET);
4545         ad.u.net.netif = ifindex;
4546         ad.u.net.family = family;
4547         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4548                 return NF_DROP;
4549
4550         if (secmark_active)
4551                 if (avc_has_perm(peer_sid, skb->secmark,
4552                                  SECCLASS_PACKET, secmark_perm, &ad))
4553                         return NF_DROP;
4554
4555         if (peerlbl_active) {
4556                 u32 if_sid;
4557                 u32 node_sid;
4558
4559                 if (sel_netif_sid(ifindex, &if_sid))
4560                         return NF_DROP;
4561                 if (avc_has_perm(peer_sid, if_sid,
4562                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4563                         return NF_DROP;
4564
4565                 if (sel_netnode_sid(addrp, family, &node_sid))
4566                         return NF_DROP;
4567                 if (avc_has_perm(peer_sid, node_sid,
4568                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4569                         return NF_DROP;
4570         }
4571
4572         return NF_ACCEPT;
4573 }
4574
4575 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4576                                            struct sk_buff *skb,
4577                                            const struct net_device *in,
4578                                            const struct net_device *out,
4579                                            int (*okfn)(struct sk_buff *))
4580 {
4581         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4582 }
4583
4584 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4585 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4586                                            struct sk_buff *skb,
4587                                            const struct net_device *in,
4588                                            const struct net_device *out,
4589                                            int (*okfn)(struct sk_buff *))
4590 {
4591         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4592 }
4593 #endif  /* IPV6 */
4594
4595 #endif  /* CONFIG_NETFILTER */
4596
4597 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4598 {
4599         int err;
4600
4601         err = cap_netlink_send(sk, skb);
4602         if (err)
4603                 return err;
4604
4605         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4606                 err = selinux_nlmsg_perm(sk, skb);
4607
4608         return err;
4609 }
4610
4611 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4612 {
4613         int err;
4614         struct avc_audit_data ad;
4615
4616         err = cap_netlink_recv(skb, capability);
4617         if (err)
4618                 return err;
4619
4620         AVC_AUDIT_DATA_INIT(&ad, CAP);
4621         ad.u.cap = capability;
4622
4623         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4624                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4625 }
4626
4627 static int ipc_alloc_security(struct task_struct *task,
4628                               struct kern_ipc_perm *perm,
4629                               u16 sclass)
4630 {
4631         struct ipc_security_struct *isec;
4632         u32 sid;
4633
4634         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4635         if (!isec)
4636                 return -ENOMEM;
4637
4638         sid = task_sid(task);
4639         isec->sclass = sclass;
4640         isec->sid = sid;
4641         perm->security = isec;
4642
4643         return 0;
4644 }
4645
4646 static void ipc_free_security(struct kern_ipc_perm *perm)
4647 {
4648         struct ipc_security_struct *isec = perm->security;
4649         perm->security = NULL;
4650         kfree(isec);
4651 }
4652
4653 static int msg_msg_alloc_security(struct msg_msg *msg)
4654 {
4655         struct msg_security_struct *msec;
4656
4657         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4658         if (!msec)
4659                 return -ENOMEM;
4660
4661         msec->sid = SECINITSID_UNLABELED;
4662         msg->security = msec;
4663
4664         return 0;
4665 }
4666
4667 static void msg_msg_free_security(struct msg_msg *msg)
4668 {
4669         struct msg_security_struct *msec = msg->security;
4670
4671         msg->security = NULL;
4672         kfree(msec);
4673 }
4674
4675 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4676                         u32 perms)
4677 {
4678         struct ipc_security_struct *isec;
4679         struct avc_audit_data ad;
4680         u32 sid = current_sid();
4681
4682         isec = ipc_perms->security;
4683
4684         AVC_AUDIT_DATA_INIT(&ad, IPC);
4685         ad.u.ipc_id = ipc_perms->key;
4686
4687         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4688 }
4689
4690 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4691 {
4692         return msg_msg_alloc_security(msg);
4693 }
4694
4695 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4696 {
4697         msg_msg_free_security(msg);
4698 }
4699
4700 /* message queue security operations */
4701 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4702 {
4703         struct ipc_security_struct *isec;
4704         struct avc_audit_data ad;
4705         u32 sid = current_sid();
4706         int rc;
4707
4708         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4709         if (rc)
4710                 return rc;
4711
4712         isec = msq->q_perm.security;
4713
4714         AVC_AUDIT_DATA_INIT(&ad, IPC);
4715         ad.u.ipc_id = msq->q_perm.key;
4716
4717         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4718                           MSGQ__CREATE, &ad);
4719         if (rc) {
4720                 ipc_free_security(&msq->q_perm);
4721                 return rc;
4722         }
4723         return 0;
4724 }
4725
4726 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4727 {
4728         ipc_free_security(&msq->q_perm);
4729 }
4730
4731 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4732 {
4733         struct ipc_security_struct *isec;
4734         struct avc_audit_data ad;
4735         u32 sid = current_sid();
4736
4737         isec = msq->q_perm.security;
4738
4739         AVC_AUDIT_DATA_INIT(&ad, IPC);
4740         ad.u.ipc_id = msq->q_perm.key;
4741
4742         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4743                             MSGQ__ASSOCIATE, &ad);
4744 }
4745
4746 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4747 {
4748         int err;
4749         int perms;
4750
4751         switch (cmd) {
4752         case IPC_INFO:
4753         case MSG_INFO:
4754                 /* No specific object, just general system-wide information. */
4755                 return task_has_system(current, SYSTEM__IPC_INFO);
4756         case IPC_STAT:
4757         case MSG_STAT:
4758                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4759                 break;
4760         case IPC_SET:
4761                 perms = MSGQ__SETATTR;
4762                 break;
4763         case IPC_RMID:
4764                 perms = MSGQ__DESTROY;
4765                 break;
4766         default:
4767                 return 0;
4768         }
4769
4770         err = ipc_has_perm(&msq->q_perm, perms);
4771         return err;
4772 }
4773
4774 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4775 {
4776         struct ipc_security_struct *isec;
4777         struct msg_security_struct *msec;
4778         struct avc_audit_data ad;
4779         u32 sid = current_sid();
4780         int rc;
4781
4782         isec = msq->q_perm.security;
4783         msec = msg->security;
4784
4785         /*
4786          * First time through, need to assign label to the message
4787          */
4788         if (msec->sid == SECINITSID_UNLABELED) {
4789                 /*
4790                  * Compute new sid based on current process and
4791                  * message queue this message will be stored in
4792                  */
4793                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4794                                              &msec->sid);
4795                 if (rc)
4796                         return rc;
4797         }
4798
4799         AVC_AUDIT_DATA_INIT(&ad, IPC);
4800         ad.u.ipc_id = msq->q_perm.key;
4801
4802         /* Can this process write to the queue? */
4803         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4804                           MSGQ__WRITE, &ad);
4805         if (!rc)
4806                 /* Can this process send the message */
4807                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4808                                   MSG__SEND, &ad);
4809         if (!rc)
4810                 /* Can the message be put in the queue? */
4811                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4812                                   MSGQ__ENQUEUE, &ad);
4813
4814         return rc;
4815 }
4816
4817 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4818                                     struct task_struct *target,
4819                                     long type, int mode)
4820 {
4821         struct ipc_security_struct *isec;
4822         struct msg_security_struct *msec;
4823         struct avc_audit_data ad;
4824         u32 sid = task_sid(target);
4825         int rc;
4826
4827         isec = msq->q_perm.security;
4828         msec = msg->security;
4829
4830         AVC_AUDIT_DATA_INIT(&ad, IPC);
4831         ad.u.ipc_id = msq->q_perm.key;
4832
4833         rc = avc_has_perm(sid, isec->sid,
4834                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4835         if (!rc)
4836                 rc = avc_has_perm(sid, msec->sid,
4837                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4838         return rc;
4839 }
4840
4841 /* Shared Memory security operations */
4842 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4843 {
4844         struct ipc_security_struct *isec;
4845         struct avc_audit_data ad;
4846         u32 sid = current_sid();
4847         int rc;
4848
4849         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4850         if (rc)
4851                 return rc;
4852
4853         isec = shp->shm_perm.security;
4854
4855         AVC_AUDIT_DATA_INIT(&ad, IPC);
4856         ad.u.ipc_id = shp->shm_perm.key;
4857
4858         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4859                           SHM__CREATE, &ad);
4860         if (rc) {
4861                 ipc_free_security(&shp->shm_perm);
4862                 return rc;
4863         }
4864         return 0;
4865 }
4866
4867 static void selinux_shm_free_security(struct shmid_kernel *shp)
4868 {
4869         ipc_free_security(&shp->shm_perm);
4870 }
4871
4872 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4873 {
4874         struct ipc_security_struct *isec;
4875         struct avc_audit_data ad;
4876         u32 sid = current_sid();
4877
4878         isec = shp->shm_perm.security;
4879
4880         AVC_AUDIT_DATA_INIT(&ad, IPC);
4881         ad.u.ipc_id = shp->shm_perm.key;
4882
4883         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4884                             SHM__ASSOCIATE, &ad);
4885 }
4886
4887 /* Note, at this point, shp is locked down */
4888 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4889 {
4890         int perms;
4891         int err;
4892
4893         switch (cmd) {
4894         case IPC_INFO:
4895         case SHM_INFO:
4896                 /* No specific object, just general system-wide information. */
4897                 return task_has_system(current, SYSTEM__IPC_INFO);
4898         case IPC_STAT:
4899         case SHM_STAT:
4900                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4901                 break;
4902         case IPC_SET:
4903                 perms = SHM__SETATTR;
4904                 break;
4905         case SHM_LOCK:
4906         case SHM_UNLOCK:
4907                 perms = SHM__LOCK;
4908                 break;
4909         case IPC_RMID:
4910                 perms = SHM__DESTROY;
4911                 break;
4912         default:
4913                 return 0;
4914         }
4915
4916         err = ipc_has_perm(&shp->shm_perm, perms);
4917         return err;
4918 }
4919
4920 static int selinux_shm_shmat(struct shmid_kernel *shp,
4921                              char __user *shmaddr, int shmflg)
4922 {
4923         u32 perms;
4924
4925         if (shmflg & SHM_RDONLY)
4926                 perms = SHM__READ;
4927         else
4928                 perms = SHM__READ | SHM__WRITE;
4929
4930         return ipc_has_perm(&shp->shm_perm, perms);
4931 }
4932
4933 /* Semaphore security operations */
4934 static int selinux_sem_alloc_security(struct sem_array *sma)
4935 {
4936         struct ipc_security_struct *isec;
4937         struct avc_audit_data ad;
4938         u32 sid = current_sid();
4939         int rc;
4940
4941         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4942         if (rc)
4943                 return rc;
4944
4945         isec = sma->sem_perm.security;
4946
4947         AVC_AUDIT_DATA_INIT(&ad, IPC);
4948         ad.u.ipc_id = sma->sem_perm.key;
4949
4950         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
4951                           SEM__CREATE, &ad);
4952         if (rc) {
4953                 ipc_free_security(&sma->sem_perm);
4954                 return rc;
4955         }
4956         return 0;
4957 }
4958
4959 static void selinux_sem_free_security(struct sem_array *sma)
4960 {
4961         ipc_free_security(&sma->sem_perm);
4962 }
4963
4964 static int selinux_sem_associate(struct sem_array *sma, int semflg)
4965 {
4966         struct ipc_security_struct *isec;
4967         struct avc_audit_data ad;
4968         u32 sid = current_sid();
4969
4970         isec = sma->sem_perm.security;
4971
4972         AVC_AUDIT_DATA_INIT(&ad, IPC);
4973         ad.u.ipc_id = sma->sem_perm.key;
4974
4975         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
4976                             SEM__ASSOCIATE, &ad);
4977 }
4978
4979 /* Note, at this point, sma is locked down */
4980 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
4981 {
4982         int err;
4983         u32 perms;
4984
4985         switch (cmd) {
4986         case IPC_INFO:
4987         case SEM_INFO:
4988                 /* No specific object, just general system-wide information. */
4989                 return task_has_system(current, SYSTEM__IPC_INFO);
4990         case GETPID:
4991         case GETNCNT:
4992         case GETZCNT:
4993                 perms = SEM__GETATTR;
4994                 break;
4995         case GETVAL:
4996         case GETALL:
4997                 perms = SEM__READ;
4998                 break;
4999         case SETVAL:
5000         case SETALL:
5001                 perms = SEM__WRITE;
5002                 break;
5003         case IPC_RMID:
5004                 perms = SEM__DESTROY;
5005                 break;
5006         case IPC_SET:
5007                 perms = SEM__SETATTR;
5008                 break;
5009         case IPC_STAT:
5010         case SEM_STAT:
5011                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5012                 break;
5013         default:
5014                 return 0;
5015         }
5016
5017         err = ipc_has_perm(&sma->sem_perm, perms);
5018         return err;
5019 }
5020
5021 static int selinux_sem_semop(struct sem_array *sma,
5022                              struct sembuf *sops, unsigned nsops, int alter)
5023 {
5024         u32 perms;
5025
5026         if (alter)
5027                 perms = SEM__READ | SEM__WRITE;
5028         else
5029                 perms = SEM__READ;
5030
5031         return ipc_has_perm(&sma->sem_perm, perms);
5032 }
5033
5034 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5035 {
5036         u32 av = 0;
5037
5038         av = 0;
5039         if (flag & S_IRUGO)
5040                 av |= IPC__UNIX_READ;
5041         if (flag & S_IWUGO)
5042                 av |= IPC__UNIX_WRITE;
5043
5044         if (av == 0)
5045                 return 0;
5046
5047         return ipc_has_perm(ipcp, av);
5048 }
5049
5050 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5051 {
5052         struct ipc_security_struct *isec = ipcp->security;
5053         *secid = isec->sid;
5054 }
5055
5056 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5057 {
5058         if (inode)
5059                 inode_doinit_with_dentry(inode, dentry);
5060 }
5061
5062 static int selinux_getprocattr(struct task_struct *p,
5063                                char *name, char **value)
5064 {
5065         const struct task_security_struct *__tsec;
5066         u32 sid;
5067         int error;
5068         unsigned len;
5069
5070         if (current != p) {
5071                 error = current_has_perm(p, PROCESS__GETATTR);
5072                 if (error)
5073                         return error;
5074         }
5075
5076         rcu_read_lock();
5077         __tsec = __task_cred(p)->security;
5078
5079         if (!strcmp(name, "current"))
5080                 sid = __tsec->sid;
5081         else if (!strcmp(name, "prev"))
5082                 sid = __tsec->osid;
5083         else if (!strcmp(name, "exec"))
5084                 sid = __tsec->exec_sid;
5085         else if (!strcmp(name, "fscreate"))
5086                 sid = __tsec->create_sid;
5087         else if (!strcmp(name, "keycreate"))
5088                 sid = __tsec->keycreate_sid;
5089         else if (!strcmp(name, "sockcreate"))
5090                 sid = __tsec->sockcreate_sid;
5091         else
5092                 goto invalid;
5093         rcu_read_unlock();
5094
5095         if (!sid)
5096                 return 0;
5097
5098         error = security_sid_to_context(sid, value, &len);
5099         if (error)
5100                 return error;
5101         return len;
5102
5103 invalid:
5104         rcu_read_unlock();
5105         return -EINVAL;
5106 }
5107
5108 static int selinux_setprocattr(struct task_struct *p,
5109                                char *name, void *value, size_t size)
5110 {
5111         struct task_security_struct *tsec;
5112         struct task_struct *tracer;
5113         struct cred *new;
5114         u32 sid = 0, ptsid;
5115         int error;
5116         char *str = value;
5117
5118         if (current != p) {
5119                 /* SELinux only allows a process to change its own
5120                    security attributes. */
5121                 return -EACCES;
5122         }
5123
5124         /*
5125          * Basic control over ability to set these attributes at all.
5126          * current == p, but we'll pass them separately in case the
5127          * above restriction is ever removed.
5128          */
5129         if (!strcmp(name, "exec"))
5130                 error = current_has_perm(p, PROCESS__SETEXEC);
5131         else if (!strcmp(name, "fscreate"))
5132                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5133         else if (!strcmp(name, "keycreate"))
5134                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5135         else if (!strcmp(name, "sockcreate"))
5136                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5137         else if (!strcmp(name, "current"))
5138                 error = current_has_perm(p, PROCESS__SETCURRENT);
5139         else
5140                 error = -EINVAL;
5141         if (error)
5142                 return error;
5143
5144         /* Obtain a SID for the context, if one was specified. */
5145         if (size && str[1] && str[1] != '\n') {
5146                 if (str[size-1] == '\n') {
5147                         str[size-1] = 0;
5148                         size--;
5149                 }
5150                 error = security_context_to_sid(value, size, &sid);
5151                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5152                         if (!capable(CAP_MAC_ADMIN))
5153                                 return error;
5154                         error = security_context_to_sid_force(value, size,
5155                                                               &sid);
5156                 }
5157                 if (error)
5158                         return error;
5159         }
5160
5161         new = prepare_creds();
5162         if (!new)
5163                 return -ENOMEM;
5164
5165         /* Permission checking based on the specified context is
5166            performed during the actual operation (execve,
5167            open/mkdir/...), when we know the full context of the
5168            operation.  See selinux_bprm_set_creds for the execve
5169            checks and may_create for the file creation checks. The
5170            operation will then fail if the context is not permitted. */
5171         tsec = new->security;
5172         if (!strcmp(name, "exec")) {
5173                 tsec->exec_sid = sid;
5174         } else if (!strcmp(name, "fscreate")) {
5175                 tsec->create_sid = sid;
5176         } else if (!strcmp(name, "keycreate")) {
5177                 error = may_create_key(sid, p);
5178                 if (error)
5179                         goto abort_change;
5180                 tsec->keycreate_sid = sid;
5181         } else if (!strcmp(name, "sockcreate")) {
5182                 tsec->sockcreate_sid = sid;
5183         } else if (!strcmp(name, "current")) {
5184                 error = -EINVAL;
5185                 if (sid == 0)
5186                         goto abort_change;
5187
5188                 /* Only allow single threaded processes to change context */
5189                 error = -EPERM;
5190                 if (!is_single_threaded(p)) {
5191                         error = security_bounded_transition(tsec->sid, sid);
5192                         if (error)
5193                                 goto abort_change;
5194                 }
5195
5196                 /* Check permissions for the transition. */
5197                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5198                                      PROCESS__DYNTRANSITION, NULL);
5199                 if (error)
5200                         goto abort_change;
5201
5202                 /* Check for ptracing, and update the task SID if ok.
5203                    Otherwise, leave SID unchanged and fail. */
5204                 ptsid = 0;
5205                 task_lock(p);
5206                 tracer = tracehook_tracer_task(p);
5207                 if (tracer)
5208                         ptsid = task_sid(tracer);
5209                 task_unlock(p);
5210
5211                 if (tracer) {
5212                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5213                                              PROCESS__PTRACE, NULL);
5214                         if (error)
5215                                 goto abort_change;
5216                 }
5217
5218                 tsec->sid = sid;
5219         } else {
5220                 error = -EINVAL;
5221                 goto abort_change;
5222         }
5223
5224         commit_creds(new);
5225         return size;
5226
5227 abort_change:
5228         abort_creds(new);
5229         return error;
5230 }
5231
5232 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5233 {
5234         return security_sid_to_context(secid, secdata, seclen);
5235 }
5236
5237 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5238 {
5239         return security_context_to_sid(secdata, seclen, secid);
5240 }
5241
5242 static void selinux_release_secctx(char *secdata, u32 seclen)
5243 {
5244         kfree(secdata);
5245 }
5246
5247 #ifdef CONFIG_KEYS
5248
5249 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5250                              unsigned long flags)
5251 {
5252         const struct task_security_struct *tsec;
5253         struct key_security_struct *ksec;
5254
5255         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5256         if (!ksec)
5257                 return -ENOMEM;
5258
5259         tsec = cred->security;
5260         if (tsec->keycreate_sid)
5261                 ksec->sid = tsec->keycreate_sid;
5262         else
5263                 ksec->sid = tsec->sid;
5264
5265         k->security = ksec;
5266         return 0;
5267 }
5268
5269 static void selinux_key_free(struct key *k)
5270 {
5271         struct key_security_struct *ksec = k->security;
5272
5273         k->security = NULL;
5274         kfree(ksec);
5275 }
5276
5277 static int selinux_key_permission(key_ref_t key_ref,
5278                                   const struct cred *cred,
5279                                   key_perm_t perm)
5280 {
5281         struct key *key;
5282         struct key_security_struct *ksec;
5283         u32 sid;
5284
5285         /* if no specific permissions are requested, we skip the
5286            permission check. No serious, additional covert channels
5287            appear to be created. */
5288         if (perm == 0)
5289                 return 0;
5290
5291         sid = cred_sid(cred);
5292
5293         key = key_ref_to_ptr(key_ref);
5294         ksec = key->security;
5295
5296         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5297 }
5298
5299 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5300 {
5301         struct key_security_struct *ksec = key->security;
5302         char *context = NULL;
5303         unsigned len;
5304         int rc;
5305
5306         rc = security_sid_to_context(ksec->sid, &context, &len);
5307         if (!rc)
5308                 rc = len;
5309         *_buffer = context;
5310         return rc;
5311 }
5312
5313 #endif
5314
5315 static struct security_operations selinux_ops = {
5316         .name =                         "selinux",
5317
5318         .ptrace_may_access =            selinux_ptrace_may_access,
5319         .ptrace_traceme =               selinux_ptrace_traceme,
5320         .capget =                       selinux_capget,
5321         .capset =                       selinux_capset,
5322         .sysctl =                       selinux_sysctl,
5323         .capable =                      selinux_capable,
5324         .quotactl =                     selinux_quotactl,
5325         .quota_on =                     selinux_quota_on,
5326         .syslog =                       selinux_syslog,
5327         .vm_enough_memory =             selinux_vm_enough_memory,
5328
5329         .netlink_send =                 selinux_netlink_send,
5330         .netlink_recv =                 selinux_netlink_recv,
5331
5332         .bprm_set_creds =               selinux_bprm_set_creds,
5333         .bprm_committing_creds =        selinux_bprm_committing_creds,
5334         .bprm_committed_creds =         selinux_bprm_committed_creds,
5335         .bprm_secureexec =              selinux_bprm_secureexec,
5336
5337         .sb_alloc_security =            selinux_sb_alloc_security,
5338         .sb_free_security =             selinux_sb_free_security,
5339         .sb_copy_data =                 selinux_sb_copy_data,
5340         .sb_kern_mount =                selinux_sb_kern_mount,
5341         .sb_show_options =              selinux_sb_show_options,
5342         .sb_statfs =                    selinux_sb_statfs,
5343         .sb_mount =                     selinux_mount,
5344         .sb_umount =                    selinux_umount,
5345         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5346         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5347         .sb_parse_opts_str =            selinux_parse_opts_str,
5348
5349
5350         .inode_alloc_security =         selinux_inode_alloc_security,
5351         .inode_free_security =          selinux_inode_free_security,
5352         .inode_init_security =          selinux_inode_init_security,
5353         .inode_create =                 selinux_inode_create,
5354         .inode_link =                   selinux_inode_link,
5355         .inode_unlink =                 selinux_inode_unlink,
5356         .inode_symlink =                selinux_inode_symlink,
5357         .inode_mkdir =                  selinux_inode_mkdir,
5358         .inode_rmdir =                  selinux_inode_rmdir,
5359         .inode_mknod =                  selinux_inode_mknod,
5360         .inode_rename =                 selinux_inode_rename,
5361         .inode_readlink =               selinux_inode_readlink,
5362         .inode_follow_link =            selinux_inode_follow_link,
5363         .inode_permission =             selinux_inode_permission,
5364         .inode_setattr =                selinux_inode_setattr,
5365         .inode_getattr =                selinux_inode_getattr,
5366         .inode_setxattr =               selinux_inode_setxattr,
5367         .inode_post_setxattr =          selinux_inode_post_setxattr,
5368         .inode_getxattr =               selinux_inode_getxattr,
5369         .inode_listxattr =              selinux_inode_listxattr,
5370         .inode_removexattr =            selinux_inode_removexattr,
5371         .inode_getsecurity =            selinux_inode_getsecurity,
5372         .inode_setsecurity =            selinux_inode_setsecurity,
5373         .inode_listsecurity =           selinux_inode_listsecurity,
5374         .inode_getsecid =               selinux_inode_getsecid,
5375
5376         .file_permission =              selinux_file_permission,
5377         .file_alloc_security =          selinux_file_alloc_security,
5378         .file_free_security =           selinux_file_free_security,
5379         .file_ioctl =                   selinux_file_ioctl,
5380         .file_mmap =                    selinux_file_mmap,
5381         .file_mprotect =                selinux_file_mprotect,
5382         .file_lock =                    selinux_file_lock,
5383         .file_fcntl =                   selinux_file_fcntl,
5384         .file_set_fowner =              selinux_file_set_fowner,
5385         .file_send_sigiotask =          selinux_file_send_sigiotask,
5386         .file_receive =                 selinux_file_receive,
5387
5388         .dentry_open =                  selinux_dentry_open,
5389
5390         .task_create =                  selinux_task_create,
5391         .cred_free =                    selinux_cred_free,
5392         .cred_prepare =                 selinux_cred_prepare,
5393         .kernel_act_as =                selinux_kernel_act_as,
5394         .kernel_create_files_as =       selinux_kernel_create_files_as,
5395         .task_setpgid =                 selinux_task_setpgid,
5396         .task_getpgid =                 selinux_task_getpgid,
5397         .task_getsid =                  selinux_task_getsid,
5398         .task_getsecid =                selinux_task_getsecid,
5399         .task_setnice =                 selinux_task_setnice,
5400         .task_setioprio =               selinux_task_setioprio,
5401         .task_getioprio =               selinux_task_getioprio,
5402         .task_setrlimit =               selinux_task_setrlimit,
5403         .task_setscheduler =            selinux_task_setscheduler,
5404         .task_getscheduler =            selinux_task_getscheduler,
5405         .task_movememory =              selinux_task_movememory,
5406         .task_kill =                    selinux_task_kill,
5407         .task_wait =                    selinux_task_wait,
5408         .task_to_inode =                selinux_task_to_inode,
5409
5410         .ipc_permission =               selinux_ipc_permission,
5411         .ipc_getsecid =                 selinux_ipc_getsecid,
5412
5413         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5414         .msg_msg_free_security =        selinux_msg_msg_free_security,
5415
5416         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5417         .msg_queue_free_security =      selinux_msg_queue_free_security,
5418         .msg_queue_associate =          selinux_msg_queue_associate,
5419         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5420         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5421         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5422
5423         .shm_alloc_security =           selinux_shm_alloc_security,
5424         .shm_free_security =            selinux_shm_free_security,
5425         .shm_associate =                selinux_shm_associate,
5426         .shm_shmctl =                   selinux_shm_shmctl,
5427         .shm_shmat =                    selinux_shm_shmat,
5428
5429         .sem_alloc_security =           selinux_sem_alloc_security,
5430         .sem_free_security =            selinux_sem_free_security,
5431         .sem_associate =                selinux_sem_associate,
5432         .sem_semctl =                   selinux_sem_semctl,
5433         .sem_semop =                    selinux_sem_semop,
5434
5435         .d_instantiate =                selinux_d_instantiate,
5436
5437         .getprocattr =                  selinux_getprocattr,
5438         .setprocattr =                  selinux_setprocattr,
5439
5440         .secid_to_secctx =              selinux_secid_to_secctx,
5441         .secctx_to_secid =              selinux_secctx_to_secid,
5442         .release_secctx =               selinux_release_secctx,
5443
5444         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5445         .unix_may_send =                selinux_socket_unix_may_send,
5446
5447         .socket_create =                selinux_socket_create,
5448         .socket_post_create =           selinux_socket_post_create,
5449         .socket_bind =                  selinux_socket_bind,
5450         .socket_connect =               selinux_socket_connect,
5451         .socket_listen =                selinux_socket_listen,
5452         .socket_accept =                selinux_socket_accept,
5453         .socket_sendmsg =               selinux_socket_sendmsg,
5454         .socket_recvmsg =               selinux_socket_recvmsg,
5455         .socket_getsockname =           selinux_socket_getsockname,
5456         .socket_getpeername =           selinux_socket_getpeername,
5457         .socket_getsockopt =            selinux_socket_getsockopt,
5458         .socket_setsockopt =            selinux_socket_setsockopt,
5459         .socket_shutdown =              selinux_socket_shutdown,
5460         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5461         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5462         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5463         .sk_alloc_security =            selinux_sk_alloc_security,
5464         .sk_free_security =             selinux_sk_free_security,
5465         .sk_clone_security =            selinux_sk_clone_security,
5466         .sk_getsecid =                  selinux_sk_getsecid,
5467         .sock_graft =                   selinux_sock_graft,
5468         .inet_conn_request =            selinux_inet_conn_request,
5469         .inet_csk_clone =               selinux_inet_csk_clone,
5470         .inet_conn_established =        selinux_inet_conn_established,
5471         .req_classify_flow =            selinux_req_classify_flow,
5472
5473 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5474         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5475         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5476         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5477         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5478         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5479         .xfrm_state_free_security =     selinux_xfrm_state_free,
5480         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5481         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5482         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5483         .xfrm_decode_session =          selinux_xfrm_decode_session,
5484 #endif
5485
5486 #ifdef CONFIG_KEYS
5487         .key_alloc =                    selinux_key_alloc,
5488         .key_free =                     selinux_key_free,
5489         .key_permission =               selinux_key_permission,
5490         .key_getsecurity =              selinux_key_getsecurity,
5491 #endif
5492
5493 #ifdef CONFIG_AUDIT
5494         .audit_rule_init =              selinux_audit_rule_init,
5495         .audit_rule_known =             selinux_audit_rule_known,
5496         .audit_rule_match =             selinux_audit_rule_match,
5497         .audit_rule_free =              selinux_audit_rule_free,
5498 #endif
5499 };
5500
5501 static __init int selinux_init(void)
5502 {
5503         if (!security_module_enable(&selinux_ops)) {
5504                 selinux_enabled = 0;
5505                 return 0;
5506         }
5507
5508         if (!selinux_enabled) {
5509                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5510                 return 0;
5511         }
5512
5513         printk(KERN_INFO "SELinux:  Initializing.\n");
5514
5515         /* Set the security state for the initial task. */
5516         cred_init_security();
5517
5518         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5519                                             sizeof(struct inode_security_struct),
5520                                             0, SLAB_PANIC, NULL);
5521         avc_init();
5522
5523         secondary_ops = security_ops;
5524         if (!secondary_ops)
5525                 panic("SELinux: No initial security operations\n");
5526         if (register_security(&selinux_ops))
5527                 panic("SELinux: Unable to register with kernel.\n");
5528
5529         if (selinux_enforcing)
5530                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5531         else
5532                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5533
5534         return 0;
5535 }
5536
5537 void selinux_complete_init(void)
5538 {
5539         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5540
5541         /* Set up any superblocks initialized prior to the policy load. */
5542         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5543         spin_lock(&sb_lock);
5544         spin_lock(&sb_security_lock);
5545 next_sb:
5546         if (!list_empty(&superblock_security_head)) {
5547                 struct superblock_security_struct *sbsec =
5548                                 list_entry(superblock_security_head.next,
5549                                            struct superblock_security_struct,
5550                                            list);
5551                 struct super_block *sb = sbsec->sb;
5552                 sb->s_count++;
5553                 spin_unlock(&sb_security_lock);
5554                 spin_unlock(&sb_lock);
5555                 down_read(&sb->s_umount);
5556                 if (sb->s_root)
5557                         superblock_doinit(sb, NULL);
5558                 drop_super(sb);
5559                 spin_lock(&sb_lock);
5560                 spin_lock(&sb_security_lock);
5561                 list_del_init(&sbsec->list);
5562                 goto next_sb;
5563         }
5564         spin_unlock(&sb_security_lock);
5565         spin_unlock(&sb_lock);
5566 }
5567
5568 /* SELinux requires early initialization in order to label
5569    all processes and objects when they are created. */
5570 security_initcall(selinux_init);
5571
5572 #if defined(CONFIG_NETFILTER)
5573
5574 static struct nf_hook_ops selinux_ipv4_ops[] = {
5575         {
5576                 .hook =         selinux_ipv4_postroute,
5577                 .owner =        THIS_MODULE,
5578                 .pf =           PF_INET,
5579                 .hooknum =      NF_INET_POST_ROUTING,
5580                 .priority =     NF_IP_PRI_SELINUX_LAST,
5581         },
5582         {
5583                 .hook =         selinux_ipv4_forward,
5584                 .owner =        THIS_MODULE,
5585                 .pf =           PF_INET,
5586                 .hooknum =      NF_INET_FORWARD,
5587                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5588         },
5589         {
5590                 .hook =         selinux_ipv4_output,
5591                 .owner =        THIS_MODULE,
5592                 .pf =           PF_INET,
5593                 .hooknum =      NF_INET_LOCAL_OUT,
5594                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5595         }
5596 };
5597
5598 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5599
5600 static struct nf_hook_ops selinux_ipv6_ops[] = {
5601         {
5602                 .hook =         selinux_ipv6_postroute,
5603                 .owner =        THIS_MODULE,
5604                 .pf =           PF_INET6,
5605                 .hooknum =      NF_INET_POST_ROUTING,
5606                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5607         },
5608         {
5609                 .hook =         selinux_ipv6_forward,
5610                 .owner =        THIS_MODULE,
5611                 .pf =           PF_INET6,
5612                 .hooknum =      NF_INET_FORWARD,
5613                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5614         }
5615 };
5616
5617 #endif  /* IPV6 */
5618
5619 static int __init selinux_nf_ip_init(void)
5620 {
5621         int err = 0;
5622
5623         if (!selinux_enabled)
5624                 goto out;
5625
5626         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5627
5628         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5629         if (err)
5630                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5631
5632 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5633         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5634         if (err)
5635                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5636 #endif  /* IPV6 */
5637
5638 out:
5639         return err;
5640 }
5641
5642 __initcall(selinux_nf_ip_init);
5643
5644 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5645 static void selinux_nf_ip_exit(void)
5646 {
5647         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5648
5649         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5650 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5651         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5652 #endif  /* IPV6 */
5653 }
5654 #endif
5655
5656 #else /* CONFIG_NETFILTER */
5657
5658 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5659 #define selinux_nf_ip_exit()
5660 #endif
5661
5662 #endif /* CONFIG_NETFILTER */
5663
5664 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5665 static int selinux_disabled;
5666
5667 int selinux_disable(void)
5668 {
5669         extern void exit_sel_fs(void);
5670
5671         if (ss_initialized) {
5672                 /* Not permitted after initial policy load. */
5673                 return -EINVAL;
5674         }
5675
5676         if (selinux_disabled) {
5677                 /* Only do this once. */
5678                 return -EINVAL;
5679         }
5680
5681         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5682
5683         selinux_disabled = 1;
5684         selinux_enabled = 0;
5685
5686         /* Reset security_ops to the secondary module, dummy or capability. */
5687         security_ops = secondary_ops;
5688
5689         /* Unregister netfilter hooks. */
5690         selinux_nf_ip_exit();
5691
5692         /* Unregister selinuxfs. */
5693         exit_sel_fs();
5694
5695         return 0;
5696 }
5697 #endif